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  <xs:element id="ldos_SharebasedPaymentAwardEquityInstrumentsOtherthanOptionsGrantsinPeriodExcludingDividendsEquivalentsWeightedAverageGrantDateFairValue" abstract="false" name="SharebasedPaymentAwardEquityInstrumentsOtherthanOptionsGrantsinPeriodExcludingDividendsEquivalentsWeightedAverageGrantDateFairValue" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:perShareItemType"/>
  <xs:element id="ldos_SharebasedCompensationArrangementbySharebasedPaymentAwardEquityInstrumentsOtherthanOptionsGrantsinPeriodWeightedAverageGrantDateFairValueMarketConditions" abstract="false" name="SharebasedCompensationArrangementbySharebasedPaymentAwardEquityInstrumentsOtherthanOptionsGrantsinPeriodWeightedAverageGrantDateFairValueMarketConditions" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:perShareItemType"/>
  <xs:element id="ldos_EffectiveIncomeTaxRateReconciliationImpactOfGoodwill" abstract="false" name="EffectiveIncomeTaxRateReconciliationImpactOfGoodwill" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ldos_EffectiveIncomeTaxRateReconciliationImpactOfForeignOperations" abstract="false" name="EffectiveIncomeTaxRateReconciliationImpactOfForeignOperations" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ldos_DeferredTaxAssetsCapitalizedResearchAndDevelopment" abstract="false" name="DeferredTaxAssetsCapitalizedResearchAndDevelopment" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ldos_DeferredTaxAssetsOperatingLeaseLiabilities" abstract="false" name="DeferredTaxAssetsOperatingLeaseLiabilities" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ldos_DeferredTaxAssetsTaxCreditAndNetOperatingLossCarryforwards" abstract="false" name="DeferredTaxAssetsTaxCreditAndNetOperatingLossCarryforwards" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ldos_OperatingLossCarryforwardsExpectedToUtilize" abstract="false" name="OperatingLossCarryforwardsExpectedToUtilize" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ldos_DeferredTaxAssetsTaxCreditCarryforwardsForeignAmountExpectedToBeUtilized" abstract="false" name="DeferredTaxAssetsTaxCreditCarryforwardsForeignAmountExpectedToBeUtilized" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ldos_LiabilityForUncertainTaxPositions" abstract="false" name="LiabilityForUncertainTaxPositions" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ldos_UnrecognizedTaxBenefitsExpectedFutureIncreaseDecrease" abstract="false" name="UnrecognizedTaxBenefitsExpectedFutureIncreaseDecrease" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ldos_PrepaidTaxesandTaxRefundReceivable" abstract="false" name="PrepaidTaxesandTaxRefundReceivable" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ldos_UkPlanMember" abstract="true" name="UkPlanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="ldos_GibbsCoxIncMember" abstract="true" name="GibbsCoxIncMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="ldos_NumberofDeferredCompensationPlans" abstract="false" name="NumberofDeferredCompensationPlans" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="ldos_NumberOfDefinedBenefitPensionPlans" abstract="false" name="NumberOfDefinedBenefitPensionPlans" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="ldos_USGovernmentMember" abstract="true" name="USGovernmentMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="ldos_DoDAndUSIntelligenceCommunityMember" abstract="true" name="DoDAndUSIntelligenceCommunityMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="ldos_SegmentOperatingIncomeLoss" abstract="false" name="SegmentOperatingIncomeLoss" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ldos_NumberOfGovernmentProcurements" abstract="false" name="NumberOfGovernmentProcurements" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="ldos_SuretyBondsOutstandingNotionalAmount" abstract="false" name="SuretyBondsOutstandingNotionalAmount" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ldos_OtherCommitmentsAndContingenciesTable" abstract="true" name="OtherCommitmentsAndContingenciesTable" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType"/>
  <xs:element id="ldos_StandbyLettersofCreditandSuretyBondsMember" abstract="true" name="StandbyLettersofCreditandSuretyBondsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="ldos_GuaranteedObligationTypeLineItems" abstract="true" name="GuaranteedObligationTypeLineItems" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
</xs:schema>
