<?xml version="1.0" encoding="US-ASCII"?>
<!--XBRL Document Created with Wdesk from Workiva-->
<!-- -->
<linkbase xsi:schemaLocation="http://www.xbrl.org/2003/linkbase http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd" xmlns="http://www.xbrl.org/2003/linkbase" xmlns:xbrldt="http://xbrl.org/2005/xbrldt" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
  <roleRef roleURI="http://www.heartlandexpress.com/role/BasisOfPresentation" xlink:href="htld-20160331.xsd#BasisOfPresentation" xlink:type="simple" />
  <roleRef roleURI="http://www.heartlandexpress.com/role/BasisOfPresentationBasisOfPresentationPolicies" xlink:href="htld-20160331.xsd#BasisOfPresentationBasisOfPresentationPolicies" xlink:type="simple" />
  <roleRef roleURI="http://www.heartlandexpress.com/role/CashAndCashEquivalents" xlink:href="htld-20160331.xsd#CashAndCashEquivalents" xlink:type="simple" />
  <roleRef roleURI="http://www.heartlandexpress.com/role/CashAndCashEquivalentsDetails" xlink:href="htld-20160331.xsd#CashAndCashEquivalentsDetails" xlink:type="simple" />
  <roleRef roleURI="http://www.heartlandexpress.com/role/CommitmentsAndContingencies" xlink:href="htld-20160331.xsd#CommitmentsAndContingencies" xlink:type="simple" />
  <roleRef roleURI="http://www.heartlandexpress.com/role/CommitmentsAndContingenciesDetails" xlink:href="htld-20160331.xsd#CommitmentsAndContingenciesDetails" xlink:type="simple" />
  <roleRef roleURI="http://www.heartlandexpress.com/role/ConsolidatedBalanceSheets" xlink:href="htld-20160331.xsd#ConsolidatedBalanceSheets" xlink:type="simple" />
  <roleRef roleURI="http://www.heartlandexpress.com/role/ConsolidatedBalanceSheetsConsolidatedBalanceSheetsParentheticals" xlink:href="htld-20160331.xsd#ConsolidatedBalanceSheetsConsolidatedBalanceSheetsParentheticals" xlink:type="simple" />
  <roleRef roleURI="http://www.heartlandexpress.com/role/ConsolidatedStatementOfStockholdersEquityParentheticals" xlink:href="htld-20160331.xsd#ConsolidatedStatementOfStockholdersEquityParentheticals" xlink:type="simple" />
  <roleRef roleURI="http://www.heartlandexpress.com/role/ConsolidatedStatementsOfCashFlows" xlink:href="htld-20160331.xsd#ConsolidatedStatementsOfCashFlows" xlink:type="simple" />
  <roleRef roleURI="http://www.heartlandexpress.com/role/ConsolidatedStatementsOfComprehensiveIncome" xlink:href="htld-20160331.xsd#ConsolidatedStatementsOfComprehensiveIncome" xlink:type="simple" />
  <roleRef roleURI="http://www.heartlandexpress.com/role/ConsolidatedStatementsOfStockholdersEquity" xlink:href="htld-20160331.xsd#ConsolidatedStatementsOfStockholdersEquity" xlink:type="simple" />
  <roleRef roleURI="http://www.heartlandexpress.com/role/DocumentAndEntityInformation" xlink:href="htld-20160331.xsd#DocumentAndEntityInformation" xlink:type="simple" />
  <roleRef roleURI="http://www.heartlandexpress.com/role/EarningsPerShare" xlink:href="htld-20160331.xsd#EarningsPerShare" xlink:type="simple" />
  <roleRef roleURI="http://www.heartlandexpress.com/role/EarningsPerShareDetails" xlink:href="htld-20160331.xsd#EarningsPerShareDetails" xlink:type="simple" />
  <roleRef roleURI="http://www.heartlandexpress.com/role/EarningsPerShareTables" xlink:href="htld-20160331.xsd#EarningsPerShareTables" xlink:type="simple" />
  <roleRef roleURI="http://www.heartlandexpress.com/role/Equity" xlink:href="htld-20160331.xsd#Equity" xlink:type="simple" />
  <roleRef roleURI="http://www.heartlandexpress.com/role/EquityDetails" xlink:href="htld-20160331.xsd#EquityDetails" xlink:type="simple" />
  <roleRef roleURI="http://www.heartlandexpress.com/role/EquityDividendsPaidDetails" xlink:href="htld-20160331.xsd#EquityDividendsPaidDetails" xlink:type="simple" />
  <roleRef roleURI="http://www.heartlandexpress.com/role/IncomeTaxes" xlink:href="htld-20160331.xsd#IncomeTaxes" xlink:type="simple" />
  <roleRef roleURI="http://www.heartlandexpress.com/role/IncomeTaxesDetails" xlink:href="htld-20160331.xsd#IncomeTaxesDetails" xlink:type="simple" />
  <roleRef roleURI="http://www.heartlandexpress.com/role/IncomeTaxesTables" xlink:href="htld-20160331.xsd#IncomeTaxesTables" xlink:type="simple" />
  <roleRef roleURI="http://www.heartlandexpress.com/role/LongTermDebt" xlink:href="htld-20160331.xsd#LongTermDebt" xlink:type="simple" />
  <roleRef roleURI="http://www.heartlandexpress.com/role/LongTermDebtDetails" xlink:href="htld-20160331.xsd#LongTermDebtDetails" xlink:type="simple" />
  <roleRef roleURI="http://www.heartlandexpress.com/role/LongTermDebtTables" xlink:href="htld-20160331.xsd#LongTermDebtTables" xlink:type="simple" />
  <roleRef roleURI="http://www.heartlandexpress.com/role/OperatingLeases" xlink:href="htld-20160331.xsd#OperatingLeases" xlink:type="simple" />
  <roleRef roleURI="http://www.heartlandexpress.com/role/OperatingLeasesDetails" xlink:href="htld-20160331.xsd#OperatingLeasesDetails" xlink:type="simple" />
  <roleRef roleURI="http://www.heartlandexpress.com/role/OtherIntangibleNetAndGoodwill" xlink:href="htld-20160331.xsd#OtherIntangibleNetAndGoodwill" xlink:type="simple" />
  <roleRef roleURI="http://www.heartlandexpress.com/role/OtherIntangibleNetAndGoodwillChangesCarryingAmountOfGoodwillDetails" xlink:href="htld-20160331.xsd#OtherIntangibleNetAndGoodwillChangesCarryingAmountOfGoodwillDetails" xlink:type="simple" />
  <roleRef roleURI="http://www.heartlandexpress.com/role/OtherIntangibleNetAndGoodwillDetails" xlink:href="htld-20160331.xsd#OtherIntangibleNetAndGoodwillDetails" xlink:type="simple" />
  <roleRef roleURI="http://www.heartlandexpress.com/role/OtherIntangibleNetAndGoodwillTables" xlink:href="htld-20160331.xsd#OtherIntangibleNetAndGoodwillTables" xlink:type="simple" />
  <roleRef roleURI="http://www.heartlandexpress.com/role/PropertyEquipmentAndDepreciation" xlink:href="htld-20160331.xsd#PropertyEquipmentAndDepreciation" xlink:type="simple" />
  <roleRef roleURI="http://www.heartlandexpress.com/role/PropertyEquipmentAndDepreciationDetails" xlink:href="htld-20160331.xsd#PropertyEquipmentAndDepreciationDetails" xlink:type="simple" />
  <roleRef roleURI="http://www.heartlandexpress.com/role/RelatedParty" xlink:href="htld-20160331.xsd#RelatedParty" xlink:type="simple" />
  <roleRef roleURI="http://www.heartlandexpress.com/role/RelatedPartyDetails" xlink:href="htld-20160331.xsd#RelatedPartyDetails" xlink:type="simple" />
  <roleRef roleURI="http://www.heartlandexpress.com/role/RelatedPartyTables" xlink:href="htld-20160331.xsd#RelatedPartyTables" xlink:type="simple" />
  <roleRef roleURI="http://www.heartlandexpress.com/role/SegmentInformation" xlink:href="htld-20160331.xsd#SegmentInformation" xlink:type="simple" />
  <roleRef roleURI="http://www.heartlandexpress.com/role/SegmentInformationDetails" xlink:href="htld-20160331.xsd#SegmentInformationDetails" xlink:type="simple" />
  <roleRef roleURI="http://www.heartlandexpress.com/role/StockBasedCompensation" xlink:href="htld-20160331.xsd#StockBasedCompensation" xlink:type="simple" />
  <roleRef roleURI="http://www.heartlandexpress.com/role/StockBasedCompensationDetails" xlink:href="htld-20160331.xsd#StockBasedCompensationDetails" xlink:type="simple" />
  <roleRef roleURI="http://www.heartlandexpress.com/role/StockBasedCompensationTables" xlink:href="htld-20160331.xsd#StockBasedCompensationTables" xlink:type="simple" />
  <roleRef roleURI="http://www.heartlandexpress.com/role/SubsequentEvents" xlink:href="htld-20160331.xsd#SubsequentEvents" xlink:type="simple" />
  <roleRef roleURI="http://www.heartlandexpress.com/role/SubsequentEventsDetails" xlink:href="htld-20160331.xsd#SubsequentEventsDetails" xlink:type="simple" />
  <roleRef roleURI="http://www.heartlandexpress.com/role/UseOfEstimates" xlink:href="htld-20160331.xsd#UseOfEstimates" xlink:type="simple" />
  <arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/all" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#all" xlink:type="simple" />
  <arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#dimension-default" xlink:type="simple" />
  <arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#dimension-domain" xlink:type="simple" />
  <arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/domain-member" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#domain-member" xlink:type="simple" />
  <arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#hypercube-dimension" xlink:type="simple" />
  <definitionLink xlink:role="http://www.heartlandexpress.com/role/BasisOfPresentation" xlink:type="extended" />
  <definitionLink xlink:role="http://www.heartlandexpress.com/role/BasisOfPresentationBasisOfPresentationPolicies" xlink:type="extended" />
  <definitionLink xlink:role="http://www.heartlandexpress.com/role/CashAndCashEquivalents" xlink:type="extended" />
  <definitionLink xlink:role="http://www.heartlandexpress.com/role/CashAndCashEquivalentsDetails" xlink:type="extended" />
  <definitionLink xlink:role="http://www.heartlandexpress.com/role/CommitmentsAndContingencies" xlink:type="extended" />
  <definitionLink xlink:role="http://www.heartlandexpress.com/role/CommitmentsAndContingenciesDetails" xlink:type="extended">
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_UnrecordedUnconditionalPurchaseObligationLineItems" xlink:label="loc_us-gaap_UnrecordedUnconditionalPurchaseObligationLineItems_7A82B454D647E18E524581EF43EA0F28" xlink:type="locator" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_UnrecordedUnconditionalPurchaseObligationTable" xlink:label="loc_us-gaap_UnrecordedUnconditionalPurchaseObligationTable_90119B1F07BCD0BD177F81EF43EA05CF" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_UnrecordedUnconditionalPurchaseObligationLineItems_7A82B454D647E18E524581EF43EA0F28" xlink:to="loc_us-gaap_UnrecordedUnconditionalPurchaseObligationTable_90119B1F07BCD0BD177F81EF43EA05CF" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_UnrecordedUnconditionalPurchaseObligationByCategoryOfItemPurchasedAxis" xlink:label="loc_us-gaap_UnrecordedUnconditionalPurchaseObligationByCategoryOfItemPurchasedAxis_F6B252458EEA8B1A709D81EF43EAE535" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_UnrecordedUnconditionalPurchaseObligationTable_90119B1F07BCD0BD177F81EF43EA05CF" xlink:to="loc_us-gaap_UnrecordedUnconditionalPurchaseObligationByCategoryOfItemPurchasedAxis_F6B252458EEA8B1A709D81EF43EAE535" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_UnconditionalPurchaseObligationCategoryOfGoodsOrServicesAcquiredDomain" xlink:label="loc_us-gaap_UnconditionalPurchaseObligationCategoryOfGoodsOrServicesAcquiredDomain_D741D0EC74AF276812D181EF43EA2234_default" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_UnrecordedUnconditionalPurchaseObligationByCategoryOfItemPurchasedAxis_F6B252458EEA8B1A709D81EF43EAE535" xlink:to="loc_us-gaap_UnconditionalPurchaseObligationCategoryOfGoodsOrServicesAcquiredDomain_D741D0EC74AF276812D181EF43EA2234_default" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_UnconditionalPurchaseObligationCategoryOfGoodsOrServicesAcquiredDomain" xlink:label="loc_us-gaap_UnconditionalPurchaseObligationCategoryOfGoodsOrServicesAcquiredDomain_D741D0EC74AF276812D181EF43EA2234" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_UnrecordedUnconditionalPurchaseObligationByCategoryOfItemPurchasedAxis_F6B252458EEA8B1A709D81EF43EAE535" xlink:to="loc_us-gaap_UnconditionalPurchaseObligationCategoryOfGoodsOrServicesAcquiredDomain_D741D0EC74AF276812D181EF43EA2234" xlink:type="arc" />
  </definitionLink>
  <definitionLink xlink:role="http://www.heartlandexpress.com/role/ConsolidatedBalanceSheets" xlink:type="extended" />
  <definitionLink xlink:role="http://www.heartlandexpress.com/role/ConsolidatedBalanceSheetsConsolidatedBalanceSheetsParentheticals" xlink:type="extended" />
  <definitionLink xlink:role="http://www.heartlandexpress.com/role/ConsolidatedStatementOfStockholdersEquityParentheticals" xlink:type="extended">
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_StatementLineItems" xlink:label="loc_us-gaap_StatementLineItems_F4BAF56B93711E136D8259E423FC04D8" xlink:type="locator" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_StatementTable" xlink:label="loc_us-gaap_StatementTable_43644EE744237150261B59E423FCB3FC" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_StatementLineItems_F4BAF56B93711E136D8259E423FC04D8" xlink:to="loc_us-gaap_StatementTable_43644EE744237150261B59E423FCB3FC" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_StatementScenarioAxis" xlink:label="loc_us-gaap_StatementScenarioAxis_CE9F9D6E4FF194CF644959E423FCCEE5" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_StatementTable_43644EE744237150261B59E423FCB3FC" xlink:to="loc_us-gaap_StatementScenarioAxis_CE9F9D6E4FF194CF644959E423FCCEE5" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_ScenarioUnspecifiedDomain" xlink:label="loc_us-gaap_ScenarioUnspecifiedDomain_C611DAFCED3DBC72C6E659E423FC3A82_default" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementScenarioAxis_CE9F9D6E4FF194CF644959E423FCCEE5" xlink:to="loc_us-gaap_ScenarioUnspecifiedDomain_C611DAFCED3DBC72C6E659E423FC3A82_default" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_ScenarioUnspecifiedDomain" xlink:label="loc_us-gaap_ScenarioUnspecifiedDomain_C611DAFCED3DBC72C6E659E423FC3A82" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementScenarioAxis_CE9F9D6E4FF194CF644959E423FCCEE5" xlink:to="loc_us-gaap_ScenarioUnspecifiedDomain_C611DAFCED3DBC72C6E659E423FC3A82" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_CommonStockDividendsPerShareDeclared" xlink:label="loc_us-gaap_CommonStockDividendsPerShareDeclared_DC46CD4C9555FED32B5A59E423FCFDB7" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_F4BAF56B93711E136D8259E423FC04D8" xlink:to="loc_us-gaap_CommonStockDividendsPerShareDeclared_DC46CD4C9555FED32B5A59E423FCFDB7" xlink:type="arc" />
  </definitionLink>
  <definitionLink xlink:role="http://www.heartlandexpress.com/role/ConsolidatedStatementsOfCashFlows" xlink:type="extended">
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_StatementLineItems" xlink:label="loc_us-gaap_StatementLineItems_38EB23BD910437C2396281D8E40224F0" xlink:type="locator" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_StatementTable" xlink:label="loc_us-gaap_StatementTable_926A4AAE0D6EBBF77EC381D8E4024FBE" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_StatementLineItems_38EB23BD910437C2396281D8E40224F0" xlink:to="loc_us-gaap_StatementTable_926A4AAE0D6EBBF77EC381D8E4024FBE" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_StatementScenarioAxis" xlink:label="loc_us-gaap_StatementScenarioAxis_E57EFA7BF2DF98744FFB81D8E402CFB6" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_StatementTable_926A4AAE0D6EBBF77EC381D8E4024FBE" xlink:to="loc_us-gaap_StatementScenarioAxis_E57EFA7BF2DF98744FFB81D8E402CFB6" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_ScenarioUnspecifiedDomain" xlink:label="loc_us-gaap_ScenarioUnspecifiedDomain_35601305A50319A053E581D8E402A585_default" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementScenarioAxis_E57EFA7BF2DF98744FFB81D8E402CFB6" xlink:to="loc_us-gaap_ScenarioUnspecifiedDomain_35601305A50319A053E581D8E402A585_default" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_ScenarioUnspecifiedDomain" xlink:label="loc_us-gaap_ScenarioUnspecifiedDomain_35601305A50319A053E581D8E402A585" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementScenarioAxis_E57EFA7BF2DF98744FFB81D8E402CFB6" xlink:to="loc_us-gaap_ScenarioUnspecifiedDomain_35601305A50319A053E581D8E402A585" xlink:type="arc" />
  </definitionLink>
  <definitionLink xlink:role="http://www.heartlandexpress.com/role/ConsolidatedStatementsOfComprehensiveIncome" xlink:type="extended" />
  <definitionLink xlink:role="http://www.heartlandexpress.com/role/ConsolidatedStatementsOfStockholdersEquity" xlink:type="extended">
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_StatementLineItems" xlink:label="loc_us-gaap_StatementLineItems_8F69AEDD09B2756E68E2780FAFEE3152" xlink:type="locator" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_StatementTable" xlink:label="loc_us-gaap_StatementTable_0361AD770812ABBE41BC780FAFEECCF9" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_StatementLineItems_8F69AEDD09B2756E68E2780FAFEE3152" xlink:to="loc_us-gaap_StatementTable_0361AD770812ABBE41BC780FAFEECCF9" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_StatementEquityComponentsAxis" xlink:label="loc_us-gaap_StatementEquityComponentsAxis_702BBB9EBD8D423FE1FF780FAFEE406A" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_StatementTable_0361AD770812ABBE41BC780FAFEECCF9" xlink:to="loc_us-gaap_StatementEquityComponentsAxis_702BBB9EBD8D423FE1FF780FAFEE406A" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_EquityComponentDomain" xlink:label="loc_us-gaap_EquityComponentDomain_6E515E3AFA3F5AF5F00E780FAFEEFEBF_default" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_702BBB9EBD8D423FE1FF780FAFEE406A" xlink:to="loc_us-gaap_EquityComponentDomain_6E515E3AFA3F5AF5F00E780FAFEEFEBF_default" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_EquityComponentDomain" xlink:label="loc_us-gaap_EquityComponentDomain_6E515E3AFA3F5AF5F00E780FAFEEFEBF" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_702BBB9EBD8D423FE1FF780FAFEE406A" xlink:to="loc_us-gaap_EquityComponentDomain_6E515E3AFA3F5AF5F00E780FAFEEFEBF" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_CommonStockMember" xlink:label="loc_us-gaap_CommonStockMember_4BD2A63EEE5180EC07A0780FAFEECFCC" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_6E515E3AFA3F5AF5F00E780FAFEEFEBF" xlink:to="loc_us-gaap_CommonStockMember_4BD2A63EEE5180EC07A0780FAFEECFCC" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_AdditionalPaidInCapitalMember" xlink:label="loc_us-gaap_AdditionalPaidInCapitalMember_6448A31B8005B38B849B780FAFEE44AB" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_6E515E3AFA3F5AF5F00E780FAFEEFEBF" xlink:to="loc_us-gaap_AdditionalPaidInCapitalMember_6448A31B8005B38B849B780FAFEE44AB" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_RetainedEarningsMember" xlink:label="loc_us-gaap_RetainedEarningsMember_ECA586EA7A7260746BFC780FAFEE51C1" xlink:type="locator" />
    <definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_6E515E3AFA3F5AF5F00E780FAFEEFEBF" xlink:to="loc_us-gaap_RetainedEarningsMember_ECA586EA7A7260746BFC780FAFEE51C1" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_TreasuryStockMember" xlink:label="loc_us-gaap_TreasuryStockMember_3D9B3AE2509DC91E7AA7780FAFEE342D" xlink:type="locator" />
    <definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_6E515E3AFA3F5AF5F00E780FAFEEFEBF" xlink:to="loc_us-gaap_TreasuryStockMember_3D9B3AE2509DC91E7AA7780FAFEE342D" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_StockholdersEquity" xlink:label="loc_us-gaap_StockholdersEquity_AD8CE3F5D86EC2BFAC0E780FAFEEDEC4" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_8F69AEDD09B2756E68E2780FAFEE3152" xlink:to="loc_us-gaap_StockholdersEquity_AD8CE3F5D86EC2BFAC0E780FAFEEDEC4" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_NetIncomeLoss" xlink:label="loc_us-gaap_NetIncomeLoss_2AD59A6FDFFA6223FA76780FAFEEE448" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_8F69AEDD09B2756E68E2780FAFEE3152" xlink:to="loc_us-gaap_NetIncomeLoss_2AD59A6FDFFA6223FA76780FAFEEE448" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_DividendsCommonStock" xlink:label="loc_us-gaap_DividendsCommonStock_CB36903D1E9D64A74E64780FAFEE2816" xlink:type="locator" />
    <definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_8F69AEDD09B2756E68E2780FAFEE3152" xlink:to="loc_us-gaap_DividendsCommonStock_CB36903D1E9D64A74E64780FAFEE2816" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_TreasuryStockValueAcquiredCostMethod" xlink:label="loc_us-gaap_TreasuryStockValueAcquiredCostMethod_7B766CB734DDFC43808E780FAFEEFC54" xlink:type="locator" />
    <definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_8F69AEDD09B2756E68E2780FAFEE3152" xlink:to="loc_us-gaap_TreasuryStockValueAcquiredCostMethod_7B766CB734DDFC43808E780FAFEEFC54" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_StockIssuedDuringPeriodValueShareBasedCompensation" xlink:label="loc_us-gaap_StockIssuedDuringPeriodValueShareBasedCompensation_6F0FD39B3477E5516D68780FAFEEE8CB" xlink:type="locator" />
    <definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_8F69AEDD09B2756E68E2780FAFEE3152" xlink:to="loc_us-gaap_StockIssuedDuringPeriodValueShareBasedCompensation_6F0FD39B3477E5516D68780FAFEEE8CB" xlink:type="arc" />
  </definitionLink>
  <definitionLink xlink:role="http://www.heartlandexpress.com/role/DocumentAndEntityInformation" xlink:type="extended">
    <loc xlink:href="http://xbrl.sec.gov/dei/2014/dei-2014-01-31.xsd#dei_DocumentInformationLineItems" xlink:label="loc_dei_DocumentInformationLineItems_D1FDAB7563CB543DE602A9EC6D5B57DC" xlink:type="locator" />
    <loc xlink:href="http://xbrl.sec.gov/dei/2014/dei-2014-01-31.xsd#dei_DocumentInformationTable" xlink:label="loc_dei_DocumentInformationTable_23B567883C0D6D228A8DA9EC6D5BB9E7" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_dei_DocumentInformationLineItems_D1FDAB7563CB543DE602A9EC6D5B57DC" xlink:to="loc_dei_DocumentInformationTable_23B567883C0D6D228A8DA9EC6D5BB9E7" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <loc xlink:href="http://xbrl.sec.gov/dei/2014/dei-2014-01-31.xsd#dei_DocumentInformationDocumentAxis" xlink:label="loc_dei_DocumentInformationDocumentAxis_FE0B027591900051384FA9EC6D5BA214" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_dei_DocumentInformationTable_23B567883C0D6D228A8DA9EC6D5BB9E7" xlink:to="loc_dei_DocumentInformationDocumentAxis_FE0B027591900051384FA9EC6D5BA214" xlink:type="arc" />
    <loc xlink:href="http://xbrl.sec.gov/dei/2014/dei-2014-01-31.xsd#dei_DocumentDomain" xlink:label="loc_dei_DocumentDomain_E056376F7E893F57A00DA9EC6D5B9B77_default" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_dei_DocumentInformationDocumentAxis_FE0B027591900051384FA9EC6D5BA214" xlink:to="loc_dei_DocumentDomain_E056376F7E893F57A00DA9EC6D5B9B77_default" xlink:type="arc" />
    <loc xlink:href="http://xbrl.sec.gov/dei/2014/dei-2014-01-31.xsd#dei_DocumentDomain" xlink:label="loc_dei_DocumentDomain_E056376F7E893F57A00DA9EC6D5B9B77" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_dei_DocumentInformationDocumentAxis_FE0B027591900051384FA9EC6D5BA214" xlink:to="loc_dei_DocumentDomain_E056376F7E893F57A00DA9EC6D5B9B77" xlink:type="arc" />
    <loc xlink:href="http://xbrl.sec.gov/dei/2014/dei-2014-01-31.xsd#dei_EntityRegistrantName" xlink:label="loc_dei_EntityRegistrantName_E75A29CD47D4B2D61B4EA9EC6D5B3D59" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_D1FDAB7563CB543DE602A9EC6D5B57DC" xlink:to="loc_dei_EntityRegistrantName_E75A29CD47D4B2D61B4EA9EC6D5B3D59" xlink:type="arc" />
    <loc xlink:href="http://xbrl.sec.gov/dei/2014/dei-2014-01-31.xsd#dei_EntityCentralIndexKey" xlink:label="loc_dei_EntityCentralIndexKey_33D54ED16DC76DFC56B5A9EC6D5BB785" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_D1FDAB7563CB543DE602A9EC6D5B57DC" xlink:to="loc_dei_EntityCentralIndexKey_33D54ED16DC76DFC56B5A9EC6D5BB785" xlink:type="arc" />
    <loc xlink:href="http://xbrl.sec.gov/dei/2014/dei-2014-01-31.xsd#dei_DocumentType" xlink:label="loc_dei_DocumentType_473DFA76B39DFB9E5BEAA9EC6D5B50C9" xlink:type="locator" />
    <definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_D1FDAB7563CB543DE602A9EC6D5B57DC" xlink:to="loc_dei_DocumentType_473DFA76B39DFB9E5BEAA9EC6D5B50C9" xlink:type="arc" />
    <loc xlink:href="http://xbrl.sec.gov/dei/2014/dei-2014-01-31.xsd#dei_DocumentPeriodEndDate" xlink:label="loc_dei_DocumentPeriodEndDate_C65A17145140BDDB8241A9EC6D5B8E60" xlink:type="locator" />
    <definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_D1FDAB7563CB543DE602A9EC6D5B57DC" xlink:to="loc_dei_DocumentPeriodEndDate_C65A17145140BDDB8241A9EC6D5B8E60" xlink:type="arc" />
    <loc xlink:href="http://xbrl.sec.gov/dei/2014/dei-2014-01-31.xsd#dei_DocumentFiscalYearFocus" xlink:label="loc_dei_DocumentFiscalYearFocus_49B1B664037B3EA19B2BA9EC6D5B3D39" xlink:type="locator" />
    <definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_D1FDAB7563CB543DE602A9EC6D5B57DC" xlink:to="loc_dei_DocumentFiscalYearFocus_49B1B664037B3EA19B2BA9EC6D5B3D39" xlink:type="arc" />
    <loc xlink:href="http://xbrl.sec.gov/dei/2014/dei-2014-01-31.xsd#dei_DocumentFiscalPeriodFocus" xlink:label="loc_dei_DocumentFiscalPeriodFocus_82600E83FD0AF401DCE4A9EC6D5BAA02" xlink:type="locator" />
    <definitionArc order="6" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_D1FDAB7563CB543DE602A9EC6D5B57DC" xlink:to="loc_dei_DocumentFiscalPeriodFocus_82600E83FD0AF401DCE4A9EC6D5BAA02" xlink:type="arc" />
    <loc xlink:href="http://xbrl.sec.gov/dei/2014/dei-2014-01-31.xsd#dei_CurrentFiscalYearEndDate" xlink:label="loc_dei_CurrentFiscalYearEndDate_58259997216A8EA7E94FA9EC6D5BDD19" xlink:type="locator" />
    <definitionArc order="7" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_D1FDAB7563CB543DE602A9EC6D5B57DC" xlink:to="loc_dei_CurrentFiscalYearEndDate_58259997216A8EA7E94FA9EC6D5BDD19" xlink:type="arc" />
    <loc xlink:href="http://xbrl.sec.gov/dei/2014/dei-2014-01-31.xsd#dei_AmendmentFlag" xlink:label="loc_dei_AmendmentFlag_6C61D6F66398B3C2A20DA9EC6D5BD76E" xlink:type="locator" />
    <definitionArc order="8" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_D1FDAB7563CB543DE602A9EC6D5B57DC" xlink:to="loc_dei_AmendmentFlag_6C61D6F66398B3C2A20DA9EC6D5BD76E" xlink:type="arc" />
    <loc xlink:href="http://xbrl.sec.gov/dei/2014/dei-2014-01-31.xsd#dei_EntityFilerCategory" xlink:label="loc_dei_EntityFilerCategory_7B61DBC4B3D3E4724A0CA9EC6D6AE059" xlink:type="locator" />
    <definitionArc order="9" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_D1FDAB7563CB543DE602A9EC6D5B57DC" xlink:to="loc_dei_EntityFilerCategory_7B61DBC4B3D3E4724A0CA9EC6D6AE059" xlink:type="arc" />
    <loc xlink:href="http://xbrl.sec.gov/dei/2014/dei-2014-01-31.xsd#dei_EntityCommonStockSharesOutstanding" xlink:label="loc_dei_EntityCommonStockSharesOutstanding_BFEAC588D8AE1E7CBB91A9EC6D6A9988" xlink:type="locator" />
    <definitionArc order="10" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_D1FDAB7563CB543DE602A9EC6D5B57DC" xlink:to="loc_dei_EntityCommonStockSharesOutstanding_BFEAC588D8AE1E7CBB91A9EC6D6A9988" xlink:type="arc" />
  </definitionLink>
  <definitionLink xlink:role="http://www.heartlandexpress.com/role/EarningsPerShare" xlink:type="extended" />
  <definitionLink xlink:role="http://www.heartlandexpress.com/role/EarningsPerShareDetails" xlink:type="extended" />
  <definitionLink xlink:role="http://www.heartlandexpress.com/role/EarningsPerShareTables" xlink:type="extended" />
  <definitionLink xlink:role="http://www.heartlandexpress.com/role/Equity" xlink:type="extended" />
  <definitionLink xlink:role="http://www.heartlandexpress.com/role/EquityDetails" xlink:type="extended" />
  <definitionLink xlink:role="http://www.heartlandexpress.com/role/EquityDividendsPaidDetails" xlink:type="extended" />
  <definitionLink xlink:role="http://www.heartlandexpress.com/role/IncomeTaxes" xlink:type="extended" />
  <definitionLink xlink:role="http://www.heartlandexpress.com/role/IncomeTaxesDetails" xlink:type="extended" />
  <definitionLink xlink:role="http://www.heartlandexpress.com/role/IncomeTaxesTables" xlink:type="extended" />
  <definitionLink xlink:role="http://www.heartlandexpress.com/role/LongTermDebt" xlink:type="extended" />
  <definitionLink xlink:role="http://www.heartlandexpress.com/role/LongTermDebtDetails" xlink:type="extended">
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_DebtInstrumentLineItems" xlink:label="loc_us-gaap_DebtInstrumentLineItems_2BC9557CE485A54199B881AE30426EAD" xlink:type="locator" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_DebtInstrumentTable" xlink:label="loc_us-gaap_DebtInstrumentTable_8C161EED11A0762C99AB81AE30421271" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DebtInstrumentLineItems_2BC9557CE485A54199B881AE30426EAD" xlink:to="loc_us-gaap_DebtInstrumentTable_8C161EED11A0762C99AB81AE30421271" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_VariableRateAxis" xlink:label="loc_us-gaap_VariableRateAxis_94898DDCDF9673D7C93B81AE3042A7AE" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_8C161EED11A0762C99AB81AE30421271" xlink:to="loc_us-gaap_VariableRateAxis_94898DDCDF9673D7C93B81AE3042A7AE" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_VariableRateDomain" xlink:label="loc_us-gaap_VariableRateDomain_844BC8891E01080D31CE81AE30427880_default" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_VariableRateAxis_94898DDCDF9673D7C93B81AE3042A7AE" xlink:to="loc_us-gaap_VariableRateDomain_844BC8891E01080D31CE81AE30427880_default" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_VariableRateDomain" xlink:label="loc_us-gaap_VariableRateDomain_844BC8891E01080D31CE81AE30427880" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_VariableRateAxis_94898DDCDF9673D7C93B81AE3042A7AE" xlink:to="loc_us-gaap_VariableRateDomain_844BC8891E01080D31CE81AE30427880" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_LondonInterbankOfferedRateLIBORMember" xlink:label="loc_us-gaap_LondonInterbankOfferedRateLIBORMember_06B56F70F8761DCF786881AE3042EBF8" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_VariableRateDomain_844BC8891E01080D31CE81AE30427880" xlink:to="loc_us-gaap_LondonInterbankOfferedRateLIBORMember_06B56F70F8761DCF786881AE3042EBF8" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_PrimeRateMember" xlink:label="loc_us-gaap_PrimeRateMember_EDA2239C95474526CE6C81AE3042CC75" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_VariableRateDomain_844BC8891E01080D31CE81AE30427880" xlink:to="loc_us-gaap_PrimeRateMember_EDA2239C95474526CE6C81AE3042CC75" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_DebtWeightedAverageInterestRate" xlink:label="loc_us-gaap_DebtWeightedAverageInterestRate_F6060BE11D9AA3351A8481AE30423C35" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_2BC9557CE485A54199B881AE30426EAD" xlink:to="loc_us-gaap_DebtWeightedAverageInterestRate_F6060BE11D9AA3351A8481AE30423C35" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity" xlink:label="loc_us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_87F02D52482849A2EBC081AE3042331C" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_2BC9557CE485A54199B881AE30426EAD" xlink:to="loc_us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_87F02D52482849A2EBC081AE3042331C" xlink:type="arc" />
    <loc xlink:href="htld-20160331.xsd#htld_LineofCreditFacilityMaximumBorrowingCapacityPeriod2" xlink:label="loc_htld_LineofCreditFacilityMaximumBorrowingCapacityPeriod2_1A541232CF6290F9C1FF81AE30422BA7" xlink:type="locator" />
    <definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_2BC9557CE485A54199B881AE30426EAD" xlink:to="loc_htld_LineofCreditFacilityMaximumBorrowingCapacityPeriod2_1A541232CF6290F9C1FF81AE30422BA7" xlink:type="arc" />
    <loc xlink:href="htld-20160331.xsd#htld_LineofCreditFacilityMaximumBorrowingCapacityPeriod3" xlink:label="loc_htld_LineofCreditFacilityMaximumBorrowingCapacityPeriod3_A7E8D727FA0451B4B36181AE30424932" xlink:type="locator" />
    <definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_2BC9557CE485A54199B881AE30426EAD" xlink:to="loc_htld_LineofCreditFacilityMaximumBorrowingCapacityPeriod3_A7E8D727FA0451B4B36181AE30424932" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_DebtInstrumentBasisSpreadOnVariableRate1" xlink:label="loc_us-gaap_DebtInstrumentBasisSpreadOnVariableRate1_B6BB752310557C35D5EF81AE304209CD" xlink:type="locator" />
    <definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_2BC9557CE485A54199B881AE30426EAD" xlink:to="loc_us-gaap_DebtInstrumentBasisSpreadOnVariableRate1_B6BB752310557C35D5EF81AE304209CD" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_LineOfCreditFacilityUnusedCapacityCommitmentFeePercentage" xlink:label="loc_us-gaap_LineOfCreditFacilityUnusedCapacityCommitmentFeePercentage_C67B80394C96C161143A81AE3042B2A7" xlink:type="locator" />
    <definitionArc order="6" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_2BC9557CE485A54199B881AE30426EAD" xlink:to="loc_us-gaap_LineOfCreditFacilityUnusedCapacityCommitmentFeePercentage_C67B80394C96C161143A81AE3042B2A7" xlink:type="arc" />
    <loc xlink:href="htld-20160331.xsd#htld_DebtInstrumentCovenantLeverageRatio" xlink:label="loc_htld_DebtInstrumentCovenantLeverageRatio_60F63284741CA46E3AA081AE3042AAD2" xlink:type="locator" />
    <definitionArc order="7" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_2BC9557CE485A54199B881AE30426EAD" xlink:to="loc_htld_DebtInstrumentCovenantLeverageRatio_60F63284741CA46E3AA081AE3042AAD2" xlink:type="arc" />
    <loc xlink:href="htld-20160331.xsd#htld_DebtCovenantMinimumNetIncomeRequirement" xlink:label="loc_htld_DebtCovenantMinimumNetIncomeRequirement_FEB273C6C7508FD42E7081AE30421AC7" xlink:type="locator" />
    <definitionArc order="8" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_2BC9557CE485A54199B881AE30426EAD" xlink:to="loc_htld_DebtCovenantMinimumNetIncomeRequirement_FEB273C6C7508FD42E7081AE30421AC7" xlink:type="arc" />
    <loc xlink:href="htld-20160331.xsd#htld_DebtCovenantMinimumTangibleNetWorth" xlink:label="loc_htld_DebtCovenantMinimumTangibleNetWorth_0134A10CFCF90322773E81AE3042896E" xlink:type="locator" />
    <definitionArc order="9" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_2BC9557CE485A54199B881AE30426EAD" xlink:to="loc_htld_DebtCovenantMinimumTangibleNetWorth_0134A10CFCF90322773E81AE3042896E" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_LineOfCredit" xlink:label="loc_us-gaap_LineOfCredit_E0CC6D8C516954DE9AAE81AE30420740" xlink:type="locator" />
    <definitionArc order="10" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_2BC9557CE485A54199B881AE30426EAD" xlink:to="loc_us-gaap_LineOfCredit_E0CC6D8C516954DE9AAE81AE30420740" xlink:type="arc" />
    <loc xlink:href="htld-20160331.xsd#htld_Lettersofcreditoutstandingonalineofcredit" xlink:label="loc_htld_Lettersofcreditoutstandingonalineofcredit_FC2E7E7451486C04877481AE30422599" xlink:type="locator" />
    <definitionArc order="11" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_2BC9557CE485A54199B881AE30426EAD" xlink:to="loc_htld_Lettersofcreditoutstandingonalineofcredit_FC2E7E7451486C04877481AE30422599" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_LineOfCreditFacilityRemainingBorrowingCapacity" xlink:label="loc_us-gaap_LineOfCreditFacilityRemainingBorrowingCapacity_E13784DCD82B36E8C68981AE30423B01" xlink:type="locator" />
    <definitionArc order="12" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_2BC9557CE485A54199B881AE30426EAD" xlink:to="loc_us-gaap_LineOfCreditFacilityRemainingBorrowingCapacity_E13784DCD82B36E8C68981AE30423B01" xlink:type="arc" />
  </definitionLink>
  <definitionLink xlink:role="http://www.heartlandexpress.com/role/LongTermDebtTables" xlink:type="extended" />
  <definitionLink xlink:role="http://www.heartlandexpress.com/role/OperatingLeases" xlink:type="extended" />
  <definitionLink xlink:role="http://www.heartlandexpress.com/role/OperatingLeasesDetails" xlink:type="extended">
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_OperatingLeasedAssetsLineItems" xlink:label="loc_us-gaap_OperatingLeasedAssetsLineItems_541BA749156B71EBB3A081B7F2CEDCCB" xlink:type="locator" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_ScheduleOfOperatingLeasedAssetsTable" xlink:label="loc_us-gaap_ScheduleOfOperatingLeasedAssetsTable_3E9189944137ECA9973C81B7F2CE292F" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_OperatingLeasedAssetsLineItems_541BA749156B71EBB3A081B7F2CEDCCB" xlink:to="loc_us-gaap_ScheduleOfOperatingLeasedAssetsTable_3E9189944137ECA9973C81B7F2CE292F" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_PropertyPlantAndEquipmentByTypeAxis" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentByTypeAxis_9F14AB7BC9103F4478CE81B7F2CEAD02" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfOperatingLeasedAssetsTable_3E9189944137ECA9973C81B7F2CE292F" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentByTypeAxis_9F14AB7BC9103F4478CE81B7F2CEAD02" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_PropertyPlantAndEquipmentTypeDomain" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_C6F3B08DABB2D10E94C081B7F2CE944F_default" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentByTypeAxis_9F14AB7BC9103F4478CE81B7F2CEAD02" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_C6F3B08DABB2D10E94C081B7F2CE944F_default" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_PropertyPlantAndEquipmentTypeDomain" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_C6F3B08DABB2D10E94C081B7F2CE944F" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentByTypeAxis_9F14AB7BC9103F4478CE81B7F2CEAD02" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_C6F3B08DABB2D10E94C081B7F2CE944F" xlink:type="arc" />
    <loc xlink:href="htld-20160331.xsd#htld_TractorsMember" xlink:label="loc_htld_TractorsMember_16B5DA867CEBDC53BA9C81B7F2CE7E26" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_C6F3B08DABB2D10E94C081B7F2CE944F" xlink:to="loc_htld_TractorsMember_16B5DA867CEBDC53BA9C81B7F2CE7E26" xlink:type="arc" />
    <loc xlink:href="htld-20160331.xsd#htld_RelatedPartyMember" xlink:label="loc_htld_RelatedPartyMember_C47918EAED74E339D51681B7F2CE7674" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_C6F3B08DABB2D10E94C081B7F2CE944F" xlink:to="loc_htld_RelatedPartyMember_C47918EAED74E339D51681B7F2CE7674" xlink:type="arc" />
    <loc xlink:href="htld-20160331.xsd#htld_TrailersMember" xlink:label="loc_htld_TrailersMember_DA4EC11CB5A0467D460581B7F2CECD33" xlink:type="locator" />
    <definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_C6F3B08DABB2D10E94C081B7F2CE944F" xlink:to="loc_htld_TrailersMember_DA4EC11CB5A0467D460581B7F2CECD33" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_BusinessAcquisitionAxis" xlink:label="loc_us-gaap_BusinessAcquisitionAxis_4140D782BCB81EC1B56581B7F2CE946D" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfOperatingLeasedAssetsTable_3E9189944137ECA9973C81B7F2CE292F" xlink:to="loc_us-gaap_BusinessAcquisitionAxis_4140D782BCB81EC1B56581B7F2CE946D" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_BusinessAcquisitionAcquireeDomain" xlink:label="loc_us-gaap_BusinessAcquisitionAcquireeDomain_35C00D0879A28C4C19B381B7F2CE6282_default" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_BusinessAcquisitionAxis_4140D782BCB81EC1B56581B7F2CE946D" xlink:to="loc_us-gaap_BusinessAcquisitionAcquireeDomain_35C00D0879A28C4C19B381B7F2CE6282_default" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_BusinessAcquisitionAcquireeDomain" xlink:label="loc_us-gaap_BusinessAcquisitionAcquireeDomain_35C00D0879A28C4C19B381B7F2CE6282" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_BusinessAcquisitionAxis_4140D782BCB81EC1B56581B7F2CE946D" xlink:to="loc_us-gaap_BusinessAcquisitionAcquireeDomain_35C00D0879A28C4C19B381B7F2CE6282" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_PropertySubjectToOrAvailableForOperatingLeaseAxis" xlink:label="loc_us-gaap_PropertySubjectToOrAvailableForOperatingLeaseAxis_5580E3AB9B02ACF6B25E81B7F2CE5547" xlink:type="locator" />
    <definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfOperatingLeasedAssetsTable_3E9189944137ECA9973C81B7F2CE292F" xlink:to="loc_us-gaap_PropertySubjectToOrAvailableForOperatingLeaseAxis_5580E3AB9B02ACF6B25E81B7F2CE5547" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_PropertySubjectToOrAvailableForOperatingLeaseDomain" xlink:label="loc_us-gaap_PropertySubjectToOrAvailableForOperatingLeaseDomain_7DEE0193C525E7D86E0281B7F2CE5997_default" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_PropertySubjectToOrAvailableForOperatingLeaseAxis_5580E3AB9B02ACF6B25E81B7F2CE5547" xlink:to="loc_us-gaap_PropertySubjectToOrAvailableForOperatingLeaseDomain_7DEE0193C525E7D86E0281B7F2CE5997_default" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_PropertySubjectToOrAvailableForOperatingLeaseDomain" xlink:label="loc_us-gaap_PropertySubjectToOrAvailableForOperatingLeaseDomain_7DEE0193C525E7D86E0281B7F2CE5997" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_PropertySubjectToOrAvailableForOperatingLeaseAxis_5580E3AB9B02ACF6B25E81B7F2CE5547" xlink:to="loc_us-gaap_PropertySubjectToOrAvailableForOperatingLeaseDomain_7DEE0193C525E7D86E0281B7F2CE5997" xlink:type="arc" />
    <loc xlink:href="htld-20160331.xsd#htld_TerminalFacilitiesMember" xlink:label="loc_htld_TerminalFacilitiesMember_1C343649122015A4549A81B7F2CE93F7" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertySubjectToOrAvailableForOperatingLeaseDomain_7DEE0193C525E7D86E0281B7F2CE5997" xlink:to="loc_htld_TerminalFacilitiesMember_1C343649122015A4549A81B7F2CE93F7" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_LeaseArrangementTypeAxis" xlink:label="loc_us-gaap_LeaseArrangementTypeAxis_80DC4251D064509D8DD181B7F2CE234D" xlink:type="locator" />
    <definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfOperatingLeasedAssetsTable_3E9189944137ECA9973C81B7F2CE292F" xlink:to="loc_us-gaap_LeaseArrangementTypeAxis_80DC4251D064509D8DD181B7F2CE234D" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_LeaseArrangementTypeDomain" xlink:label="loc_us-gaap_LeaseArrangementTypeDomain_8A8EF47AFDC3B2C33DB281B7F2CED134_default" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_LeaseArrangementTypeAxis_80DC4251D064509D8DD181B7F2CE234D" xlink:to="loc_us-gaap_LeaseArrangementTypeDomain_8A8EF47AFDC3B2C33DB281B7F2CED134_default" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_LeaseArrangementTypeDomain" xlink:label="loc_us-gaap_LeaseArrangementTypeDomain_8A8EF47AFDC3B2C33DB281B7F2CED134" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_LeaseArrangementTypeAxis_80DC4251D064509D8DD181B7F2CE234D" xlink:to="loc_us-gaap_LeaseArrangementTypeDomain_8A8EF47AFDC3B2C33DB281B7F2CED134" xlink:type="arc" />
    <loc xlink:href="htld-20160331.xsd#htld_RelatedPartyMember" xlink:label="loc_htld_RelatedPartyMember_597E28881996ED03C3AC81B7F2CE8731" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LeaseArrangementTypeDomain_8A8EF47AFDC3B2C33DB281B7F2CED134" xlink:to="loc_htld_RelatedPartyMember_597E28881996ED03C3AC81B7F2CE8731" xlink:type="arc" />
    <loc xlink:href="htld-20160331.xsd#htld_TrailersMember" xlink:label="loc_htld_TrailersMember_3F024D847F0E0802570F81B7F2CE132D" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LeaseArrangementTypeDomain_8A8EF47AFDC3B2C33DB281B7F2CED134" xlink:to="loc_htld_TrailersMember_3F024D847F0E0802570F81B7F2CE132D" xlink:type="arc" />
    <loc xlink:href="htld-20160331.xsd#htld_FairValueOfRevenueEquipmentTraded" xlink:label="loc_htld_FairValueOfRevenueEquipmentTraded_08DC95BCF6AB3B3AF60681B7F2CEAF62" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OperatingLeasedAssetsLineItems_541BA749156B71EBB3A081B7F2CEDCCB" xlink:to="loc_htld_FairValueOfRevenueEquipmentTraded_08DC95BCF6AB3B3AF60681B7F2CEAF62" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_LeaseAndRentalExpense" xlink:label="loc_us-gaap_LeaseAndRentalExpense_D0ABD7821AF499EDC65481B7F2CE93F6" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OperatingLeasedAssetsLineItems_541BA749156B71EBB3A081B7F2CEDCCB" xlink:to="loc_us-gaap_LeaseAndRentalExpense_D0ABD7821AF499EDC65481B7F2CE93F6" xlink:type="arc" />
  </definitionLink>
  <definitionLink xlink:role="http://www.heartlandexpress.com/role/OtherIntangibleNetAndGoodwill" xlink:type="extended" />
  <definitionLink xlink:role="http://www.heartlandexpress.com/role/OtherIntangibleNetAndGoodwillChangesCarryingAmountOfGoodwillDetails" xlink:type="extended" />
  <definitionLink xlink:role="http://www.heartlandexpress.com/role/OtherIntangibleNetAndGoodwillDetails" xlink:type="extended">
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsLineItems" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsLineItems_7E5C6CBCE463C3E5F2B381F06F004CFD" xlink:type="locator" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable" xlink:label="loc_us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable_DA93E20BEF0B7D6E7AD681F06F008290" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsLineItems_7E5C6CBCE463C3E5F2B381F06F004CFD" xlink:to="loc_us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable_DA93E20BEF0B7D6E7AD681F06F008290" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_76EA7535746135FF5A5D81F06F007305" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable_DA93E20BEF0B7D6E7AD681F06F008290" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_76EA7535746135FF5A5D81F06F007305" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_9D81123FA79D0B74E12F81F06F00828E_default" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_76EA7535746135FF5A5D81F06F007305" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_9D81123FA79D0B74E12F81F06F00828E_default" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_9D81123FA79D0B74E12F81F06F00828E" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_76EA7535746135FF5A5D81F06F007305" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_9D81123FA79D0B74E12F81F06F00828E" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_CustomerRelationshipsMember" xlink:label="loc_us-gaap_CustomerRelationshipsMember_80891B90C031BE6710DE81F06F000C25" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_9D81123FA79D0B74E12F81F06F00828E" xlink:to="loc_us-gaap_CustomerRelationshipsMember_80891B90C031BE6710DE81F06F000C25" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_TradeNamesMember" xlink:label="loc_us-gaap_TradeNamesMember_7C3315F778BD6F24CD4581F06F00C799" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_9D81123FA79D0B74E12F81F06F00828E" xlink:to="loc_us-gaap_TradeNamesMember_7C3315F778BD6F24CD4581F06F00C799" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_NoncompeteAgreementsMember" xlink:label="loc_us-gaap_NoncompeteAgreementsMember_A90319220EDCBEF67D1E81F06F00E0B1" xlink:type="locator" />
    <definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_9D81123FA79D0B74E12F81F06F00828E" xlink:to="loc_us-gaap_NoncompeteAgreementsMember_A90319220EDCBEF67D1E81F06F00E0B1" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_RealEstateMember" xlink:label="loc_us-gaap_RealEstateMember_65B698C92299DA5CAB3681F06F001F12" xlink:type="locator" />
    <definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_9D81123FA79D0B74E12F81F06F00828E" xlink:to="loc_us-gaap_RealEstateMember_65B698C92299DA5CAB3681F06F001F12" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetUsefulLife" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetUsefulLife_11A87D0167E88AE1272A81F06F006CFA" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsLineItems_7E5C6CBCE463C3E5F2B381F06F004CFD" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetUsefulLife_11A87D0167E88AE1272A81F06F006CFA" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsGross" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsGross_2958B348C5819D84A41581F06F000B6F" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsLineItems_7E5C6CBCE463C3E5F2B381F06F004CFD" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsGross_2958B348C5819D84A41581F06F000B6F" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization_DE5EE681DEDA8B40675A81F06F00CEB8" xlink:type="locator" />
    <definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsLineItems_7E5C6CBCE463C3E5F2B381F06F004CFD" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization_DE5EE681DEDA8B40675A81F06F00CEB8" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsNet" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsNet_6D2A22F76615787CCC1C81F06F00E23E" xlink:type="locator" />
    <definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsLineItems_7E5C6CBCE463C3E5F2B381F06F004CFD" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsNet_6D2A22F76615787CCC1C81F06F00E23E" xlink:type="arc" />
  </definitionLink>
  <definitionLink xlink:role="http://www.heartlandexpress.com/role/OtherIntangibleNetAndGoodwillTables" xlink:type="extended" />
  <definitionLink xlink:role="http://www.heartlandexpress.com/role/PropertyEquipmentAndDepreciation" xlink:type="extended" />
  <definitionLink xlink:role="http://www.heartlandexpress.com/role/PropertyEquipmentAndDepreciationDetails" xlink:type="extended">
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_PropertyPlantAndEquipmentLineItems" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentLineItems_543F0F0BA2553ED8DB3562B9B4788998" xlink:type="locator" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_ScheduleOfPropertyPlantAndEquipmentTable" xlink:label="loc_us-gaap_ScheduleOfPropertyPlantAndEquipmentTable_C674935BAAE23FBCBEAE62B9B478B548" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentLineItems_543F0F0BA2553ED8DB3562B9B4788998" xlink:to="loc_us-gaap_ScheduleOfPropertyPlantAndEquipmentTable_C674935BAAE23FBCBEAE62B9B478B548" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <loc xlink:href="htld-20160331.xsd#htld_FinancialStatementLocationAxis" xlink:label="loc_htld_FinancialStatementLocationAxis_117B4778421D470DB70562B9B478FCD6" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfPropertyPlantAndEquipmentTable_C674935BAAE23FBCBEAE62B9B478B548" xlink:to="loc_htld_FinancialStatementLocationAxis_117B4778421D470DB70562B9B478FCD6" xlink:type="arc" />
    <loc xlink:href="htld-20160331.xsd#htld_FinancialStatementLocationDomain" xlink:label="loc_htld_FinancialStatementLocationDomain_E227110C39C386F2073C62B9B47875C0_default" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_htld_FinancialStatementLocationAxis_117B4778421D470DB70562B9B478FCD6" xlink:to="loc_htld_FinancialStatementLocationDomain_E227110C39C386F2073C62B9B47875C0_default" xlink:type="arc" />
    <loc xlink:href="htld-20160331.xsd#htld_FinancialStatementLocationDomain" xlink:label="loc_htld_FinancialStatementLocationDomain_E227110C39C386F2073C62B9B47875C0" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_htld_FinancialStatementLocationAxis_117B4778421D470DB70562B9B478FCD6" xlink:to="loc_htld_FinancialStatementLocationDomain_E227110C39C386F2073C62B9B47875C0" xlink:type="arc" />
    <loc xlink:href="htld-20160331.xsd#htld_CommunicationsAndUtilitiesExpenseMember" xlink:label="loc_htld_CommunicationsAndUtilitiesExpenseMember_4915B7257DD4EC24DB0D62B9B478EA95" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_htld_FinancialStatementLocationDomain_E227110C39C386F2073C62B9B47875C0" xlink:to="loc_htld_CommunicationsAndUtilitiesExpenseMember_4915B7257DD4EC24DB0D62B9B478EA95" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_PropertyPlantAndEquipmentByTypeAxis" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentByTypeAxis_4C848C24FCB0A1164D4762B9B4789FF8" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfPropertyPlantAndEquipmentTable_C674935BAAE23FBCBEAE62B9B478B548" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentByTypeAxis_4C848C24FCB0A1164D4762B9B4789FF8" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_PropertyPlantAndEquipmentTypeDomain" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_4A83AB10D02043D9887662B9B478FE81_default" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentByTypeAxis_4C848C24FCB0A1164D4762B9B4789FF8" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_4A83AB10D02043D9887662B9B478FE81_default" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_PropertyPlantAndEquipmentTypeDomain" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_4A83AB10D02043D9887662B9B478FE81" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentByTypeAxis_4C848C24FCB0A1164D4762B9B4789FF8" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_4A83AB10D02043D9887662B9B478FE81" xlink:type="arc" />
    <loc xlink:href="htld-20160331.xsd#htld_TractorsMember" xlink:label="loc_htld_TractorsMember_14F0DCA525CE1978EEFD62B9B47856C8" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_4A83AB10D02043D9887662B9B478FE81" xlink:to="loc_htld_TractorsMember_14F0DCA525CE1978EEFD62B9B47856C8" xlink:type="arc" />
    <loc xlink:href="htld-20160331.xsd#htld_TrailersMember" xlink:label="loc_htld_TrailersMember_918CB1C6432C3371D87B62B9B4787CF2" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_4A83AB10D02043D9887662B9B478FE81" xlink:to="loc_htld_TrailersMember_918CB1C6432C3371D87B62B9B4787CF2" xlink:type="arc" />
    <loc xlink:href="htld-20160331.xsd#htld_AmortizationPeriodOfTires" xlink:label="loc_htld_AmortizationPeriodOfTires_29E76D99DAD4B6DD61C762B9B4780E00" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentLineItems_543F0F0BA2553ED8DB3562B9B4788998" xlink:to="loc_htld_AmortizationPeriodOfTires_29E76D99DAD4B6DD61C762B9B4780E00" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_Depreciation" xlink:label="loc_us-gaap_Depreciation_AEF2A0063A6435D7545762B9B4788D5B" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentLineItems_543F0F0BA2553ED8DB3562B9B4788998" xlink:to="loc_us-gaap_Depreciation_AEF2A0063A6435D7545762B9B4788D5B" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_PropertyPlantAndEquipmentSalvageValue" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentSalvageValue_F6A7A98B73BAD14B445F62B9B478F8C5" xlink:type="locator" />
    <definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentLineItems_543F0F0BA2553ED8DB3562B9B4788998" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentSalvageValue_F6A7A98B73BAD14B445F62B9B478F8C5" xlink:type="arc" />
  </definitionLink>
  <definitionLink xlink:role="http://www.heartlandexpress.com/role/RelatedParty" xlink:type="extended" />
  <definitionLink xlink:role="http://www.heartlandexpress.com/role/RelatedPartyDetails" xlink:type="extended">
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_RelatedPartyTransactionLineItems" xlink:label="loc_us-gaap_RelatedPartyTransactionLineItems_509205764EF3393F1D9F81E336C35CBD" xlink:type="locator" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable" xlink:label="loc_us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable_F6EDE50618C0ED31810581E336C28DC4" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_509205764EF3393F1D9F81E336C35CBD" xlink:to="loc_us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable_F6EDE50618C0ED31810581E336C28DC4" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_PropertySubjectToOrAvailableForOperatingLeaseAxis" xlink:label="loc_us-gaap_PropertySubjectToOrAvailableForOperatingLeaseAxis_4ED37D70E1745A53227D81E336C283B0" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable_F6EDE50618C0ED31810581E336C28DC4" xlink:to="loc_us-gaap_PropertySubjectToOrAvailableForOperatingLeaseAxis_4ED37D70E1745A53227D81E336C283B0" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_PropertySubjectToOrAvailableForOperatingLeaseDomain" xlink:label="loc_us-gaap_PropertySubjectToOrAvailableForOperatingLeaseDomain_2D20805B54643E24E1A381E336C23A44_default" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_PropertySubjectToOrAvailableForOperatingLeaseAxis_4ED37D70E1745A53227D81E336C283B0" xlink:to="loc_us-gaap_PropertySubjectToOrAvailableForOperatingLeaseDomain_2D20805B54643E24E1A381E336C23A44_default" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_PropertySubjectToOrAvailableForOperatingLeaseDomain" xlink:label="loc_us-gaap_PropertySubjectToOrAvailableForOperatingLeaseDomain_2D20805B54643E24E1A381E336C23A44" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_PropertySubjectToOrAvailableForOperatingLeaseAxis_4ED37D70E1745A53227D81E336C283B0" xlink:to="loc_us-gaap_PropertySubjectToOrAvailableForOperatingLeaseDomain_2D20805B54643E24E1A381E336C23A44" xlink:type="arc" />
    <loc xlink:href="htld-20160331.xsd#htld_TerminalFacilitiesMember" xlink:label="loc_htld_TerminalFacilitiesMember_0985CB7F81A5FD062F2F81E336C3B9E7" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertySubjectToOrAvailableForOperatingLeaseDomain_2D20805B54643E24E1A381E336C23A44" xlink:to="loc_htld_TerminalFacilitiesMember_0985CB7F81A5FD062F2F81E336C3B9E7" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_LeaseArrangementTypeAxis" xlink:label="loc_us-gaap_LeaseArrangementTypeAxis_B40944FFF686E35A2BBE81E336C399C7" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable_F6EDE50618C0ED31810581E336C28DC4" xlink:to="loc_us-gaap_LeaseArrangementTypeAxis_B40944FFF686E35A2BBE81E336C399C7" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_LeaseArrangementTypeDomain" xlink:label="loc_us-gaap_LeaseArrangementTypeDomain_5C01CECAC4DB4773B1F581E336C3F28B_default" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_LeaseArrangementTypeAxis_B40944FFF686E35A2BBE81E336C399C7" xlink:to="loc_us-gaap_LeaseArrangementTypeDomain_5C01CECAC4DB4773B1F581E336C3F28B_default" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_LeaseArrangementTypeDomain" xlink:label="loc_us-gaap_LeaseArrangementTypeDomain_5C01CECAC4DB4773B1F581E336C3F28B" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_LeaseArrangementTypeAxis_B40944FFF686E35A2BBE81E336C399C7" xlink:to="loc_us-gaap_LeaseArrangementTypeDomain_5C01CECAC4DB4773B1F581E336C3F28B" xlink:type="arc" />
    <loc xlink:href="htld-20160331.xsd#htld_RelatedPartyMember" xlink:label="loc_htld_RelatedPartyMember_1DCDB849B716974AC5E481E336C316CF" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LeaseArrangementTypeDomain_5C01CECAC4DB4773B1F581E336C3F28B" xlink:to="loc_htld_RelatedPartyMember_1DCDB849B716974AC5E481E336C316CF" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_DueToRelatedPartiesCurrent" xlink:label="loc_us-gaap_DueToRelatedPartiesCurrent_B595B118DE8740888CCC81E336C3AE05" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_509205764EF3393F1D9F81E336C35CBD" xlink:to="loc_us-gaap_DueToRelatedPartiesCurrent_B595B118DE8740888CCC81E336C3AE05" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_PaymentsToAcquireMachineryAndEquipment" xlink:label="loc_us-gaap_PaymentsToAcquireMachineryAndEquipment_0B1BA2CEAB3A4B34567F81E336C323EF" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_509205764EF3393F1D9F81E336C35CBD" xlink:to="loc_us-gaap_PaymentsToAcquireMachineryAndEquipment_0B1BA2CEAB3A4B34567F81E336C323EF" xlink:type="arc" />
    <loc xlink:href="htld-20160331.xsd#htld_Receiptsfortractorsales" xlink:label="loc_htld_Receiptsfortractorsales_735D61B16C4EADA6C5AB81E336C38235" xlink:type="locator" />
    <definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_509205764EF3393F1D9F81E336C35CBD" xlink:to="loc_htld_Receiptsfortractorsales_735D61B16C4EADA6C5AB81E336C38235" xlink:type="arc" />
    <loc xlink:href="htld-20160331.xsd#htld_Receiptsfortrailersales" xlink:label="loc_htld_Receiptsfortrailersales_AFEC69C0CC20D906BE7081E336C32CB6" xlink:type="locator" />
    <definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_509205764EF3393F1D9F81E336C35CBD" xlink:to="loc_htld_Receiptsfortrailersales_AFEC69C0CC20D906BE7081E336C32CB6" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_LeaseAndRentalExpense" xlink:label="loc_us-gaap_LeaseAndRentalExpense_91E2E9926EC71BF1BDBC81E336C368DC" xlink:type="locator" />
    <definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_509205764EF3393F1D9F81E336C35CBD" xlink:to="loc_us-gaap_LeaseAndRentalExpense_91E2E9926EC71BF1BDBC81E336C368DC" xlink:type="arc" />
    <loc xlink:href="htld-20160331.xsd#htld_Paymentsforpartsandservices" xlink:label="loc_htld_Paymentsforpartsandservices_74526D267A4FBB6D7F4181E336C36BBA" xlink:type="locator" />
    <definitionArc order="6" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_509205764EF3393F1D9F81E336C35CBD" xlink:to="loc_htld_Paymentsforpartsandservices_74526D267A4FBB6D7F4181E336C36BBA" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_AdministrativeServicesRevenue" xlink:label="loc_us-gaap_AdministrativeServicesRevenue_CA970243E158B654F81381E336C3DA2B" xlink:type="locator" />
    <definitionArc order="7" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_509205764EF3393F1D9F81E336C35CBD" xlink:to="loc_us-gaap_AdministrativeServicesRevenue_CA970243E158B654F81381E336C3DA2B" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_DueFromRelatedPartiesCurrent" xlink:label="loc_us-gaap_DueFromRelatedPartiesCurrent_02BD9BDDDD39DFBF5F6781E336C3B8ED" xlink:type="locator" />
    <definitionArc order="8" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_509205764EF3393F1D9F81E336C35CBD" xlink:to="loc_us-gaap_DueFromRelatedPartiesCurrent_02BD9BDDDD39DFBF5F6781E336C3B8ED" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_CostsAndExpensesRelatedParty" xlink:label="loc_us-gaap_CostsAndExpensesRelatedParty_0DDE8089531769556D2F81E336C37B4C" xlink:type="locator" />
    <definitionArc order="9" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_509205764EF3393F1D9F81E336C35CBD" xlink:to="loc_us-gaap_CostsAndExpensesRelatedParty_0DDE8089531769556D2F81E336C37B4C" xlink:type="arc" />
  </definitionLink>
  <definitionLink xlink:role="http://www.heartlandexpress.com/role/RelatedPartyTables" xlink:type="extended" />
  <definitionLink xlink:role="http://www.heartlandexpress.com/role/SegmentInformation" xlink:type="extended" />
  <definitionLink xlink:role="http://www.heartlandexpress.com/role/SegmentInformationDetails" xlink:type="extended" />
  <definitionLink xlink:role="http://www.heartlandexpress.com/role/StockBasedCompensation" xlink:type="extended" />
  <definitionLink xlink:role="http://www.heartlandexpress.com/role/StockBasedCompensationDetails" xlink:type="extended">
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_7F51D39F750D8AA7BF3C81B5C4B4453D" xlink:type="locator" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable" xlink:label="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_535E30B1BA3E34C134DC81B5C4B47EDB" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_7F51D39F750D8AA7BF3C81B5C4B4453D" xlink:to="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_535E30B1BA3E34C134DC81B5C4B47EDB" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_RangeAxis" xlink:label="loc_us-gaap_RangeAxis_0376268C16215DA343A881B5C4B49732" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_535E30B1BA3E34C134DC81B5C4B47EDB" xlink:to="loc_us-gaap_RangeAxis_0376268C16215DA343A881B5C4B49732" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_RangeMember" xlink:label="loc_us-gaap_RangeMember_B418C7B0E13367B0DE5881B5C4B497C2_default" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_RangeAxis_0376268C16215DA343A881B5C4B49732" xlink:to="loc_us-gaap_RangeMember_B418C7B0E13367B0DE5881B5C4B497C2_default" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_RangeMember" xlink:label="loc_us-gaap_RangeMember_B418C7B0E13367B0DE5881B5C4B497C2" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_RangeAxis_0376268C16215DA343A881B5C4B49732" xlink:to="loc_us-gaap_RangeMember_B418C7B0E13367B0DE5881B5C4B497C2" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_MaximumMember" xlink:label="loc_us-gaap_MaximumMember_007AEC3E0E0E809C377C81B5C4B43F1C" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RangeMember_B418C7B0E13367B0DE5881B5C4B497C2" xlink:to="loc_us-gaap_MaximumMember_007AEC3E0E0E809C377C81B5C4B43F1C" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_MinimumMember" xlink:label="loc_us-gaap_MinimumMember_5E30AD4EE20F365C04D981B5C4B47D67" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RangeMember_B418C7B0E13367B0DE5881B5C4B497C2" xlink:to="loc_us-gaap_MinimumMember_5E30AD4EE20F365C04D981B5C4B47D67" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue_B606EFD3232CE805BDF581B5C4B4EBC4" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_7F51D39F750D8AA7BF3C81B5C4B4453D" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue_B606EFD3232CE805BDF581B5C4B4EBC4" xlink:type="arc" />
    <loc xlink:href="htld-20160331.xsd#htld_Weightedaveragefairvaluepriceofstockawardslower" xlink:label="loc_htld_Weightedaveragefairvaluepriceofstockawardslower_3AEA67EDF5959E19743D81B5C4B4C065" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_7F51D39F750D8AA7BF3C81B5C4B4453D" xlink:to="loc_htld_Weightedaveragefairvaluepriceofstockawardslower_3AEA67EDF5959E19743D81B5C4B4C065" xlink:type="arc" />
    <loc xlink:href="htld-20160331.xsd#htld_Weightedaveragefairvaluepriceofstockawardsupper" xlink:label="loc_htld_Weightedaveragefairvaluepriceofstockawardsupper_7F2BF844BE80E6110F7981B5C4B4A98D" xlink:type="locator" />
    <definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_7F51D39F750D8AA7BF3C81B5C4B4453D" xlink:to="loc_htld_Weightedaveragefairvaluepriceofstockawardsupper_7F2BF844BE80E6110F7981B5C4B4A98D" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod_AEAAE2FF77B49B08FB6581CC890BEF68" xlink:type="locator" />
    <definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_7F51D39F750D8AA7BF3C81B5C4B4453D" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod_AEAAE2FF77B49B08FB6581CC890BEF68" xlink:type="arc" />
  </definitionLink>
  <definitionLink xlink:role="http://www.heartlandexpress.com/role/StockBasedCompensationTables" xlink:type="extended" />
  <definitionLink xlink:role="http://www.heartlandexpress.com/role/SubsequentEvents" xlink:type="extended" />
  <definitionLink xlink:role="http://www.heartlandexpress.com/role/SubsequentEventsDetails" xlink:type="extended" />
  <definitionLink xlink:role="http://www.heartlandexpress.com/role/UseOfEstimates" xlink:type="extended" />
</linkbase>