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<edgarSubmission xmlns="http://www.sec.gov/edgar/ncen">
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    <filerInfo>
      <liveTestFlag>LIVE</liveTestFlag>
      <filer>
        <issuerCredentials>
          <cik>0000917677</cik>
          <ccc>XXXXXXXX</ccc>
        </issuerCredentials>
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      <flags>
        <returnCopyFlag>false</returnCopyFlag>
        <overrideInternetFlag>false</overrideInternetFlag>
        <confirmingCopyFlag>false</confirmingCopyFlag>
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      <investmentCompanyType>N-6</investmentCompanyType>
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    <seriesClass>
      <reportClass>
        <rptIncludeAllClassesFlag>true</rptIncludeAllClassesFlag>
      </reportClass>
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    <generalInfo isReportPeriodLt12="N" reportEndingPeriod="2019-12-31"/>
    <registrantInfo>
      <registrantFullName>SECURITY LIFE SEPARATE ACCOUNT L1</registrantFullName>
      <investmentCompFileNo>811-08292</investmentCompFileNo>
      <registrantCik>0000917677</registrantCik>
      <registrantLei>00000000000000000000</registrantLei>
      <registrantstreet1>8055 East Tufts Avenue, Suite 710</registrantstreet1>
      <registrantcity>Denver</registrantcity>
      <registrantzipCode>80237</registrantzipCode>
      <registrantstate>US-CO</registrantstate>
      <registrantcountry>US</registrantcountry>
      <registrantphoneNumber>770-980-5386</registrantphoneNumber>
      <websites>
        <website webpage="www.voya.com"/>
      </websites>
      <locationBooksRecords>
        <locationBooksRecord>
          <officeName>Security Life of Denver Insurance Company</officeName>
          <officeAddress1>5780 Powers Ferry Road NW</officeAddress1>
          <officeCity>Atlanta</officeCity>
          <officeStateCountry officeState="US-GA" officeCountry="US"/>
          <officeRecordsZipCode>30327</officeRecordsZipCode>
          <officePhone>770-980-5386</officePhone>
          <booksRecordsDesc>Atlanta prepares the financial statements for the Company and coordinates with other locations to obtain the necessary information to form the basis for the financial statements.</booksRecordsDesc>
        </locationBooksRecord>
      </locationBooksRecords>
      <isRegistrantFirstFiling>N</isRegistrantFirstFiling>
      <isRegistrantLastFiling>N</isRegistrantLastFiling>
      <registrantFamilyInvComp isRegistrantFamilyInvComp="Y" familyInvCompFullName="Registered Separate Accounts of Security Life of Denver Insurance Company"/>
      <registrantClassificationType>N-6</registrantClassificationType>
      <isSecuritiesActRegistration>Y</isSecuritiesActRegistration>
      <chiefComplianceOfficers>
        <chiefComplianceOfficer>
          <ccoName>Chad M. Eslinger</ccoName>
          <crdNumber>004182299</crdNumber>
          <ccoStreet1>20 Washington Ave South</ccoStreet1>
          <ccoCity>Minneapolis</ccoCity>
          <ccoStateCountry ccoCountry="US" ccoState="US-MN"/>
          <ccoZipCode>55401</ccoZipCode>
          <ccoPhone>XXXXXX</ccoPhone>
          <isCcoChangedSinceLastFiling>N</isCcoChangedSinceLastFiling>
          <ccoEmployers>
            <ccoEmployer ccoEmployerId="N/A" ccoEmployerName="N/A"/>
          </ccoEmployers>
        </chiefComplianceOfficer>
      </chiefComplianceOfficers>
      <isRegistrantSubmittedMatter>N</isRegistrantSubmittedMatter>
      <isPreviousLegalProceeding>N</isPreviousLegalProceeding>
      <isPreviousProceedingTerminated>N</isPreviousProceedingTerminated>
      <isFinancialSupportDuringPeriod>N</isFinancialSupportDuringPeriod>
      <isExemptionFromAct>N</isExemptionFromAct>
      <principalUnderwriters>
        <principalUnderwriter>
          <principalUnderwriterName>Voya America Equities, Inc.</principalUnderwriterName>
          <principalUnderwriterFileNumber>008-47089</principalUnderwriterFileNumber>
          <principalUnderwriterCrdNumber>000036259</principalUnderwriterCrdNumber>
          <principalUnderwriterLei>N/A</principalUnderwriterLei>
          <principalUnderWriterStateCountry principalUnderWriterState="US-CO" principalUnderWriterCountry="US"/>
          <isPrincipalUnderwriterAffiliatedWithRegistrant>Y</isPrincipalUnderwriterAffiliatedWithRegistrant>
        </principalUnderwriter>
      </principalUnderwriters>
      <isUnderwriterHiredOrTerminated>N</isUnderwriterHiredOrTerminated>
      <publicAccountants>
        <publicAccountant>
          <publicAccountantName>Ernst &amp; Young, LLP</publicAccountantName>
          <pcaobNumber>42</pcaobNumber>
          <publicAccountantLei>N/A</publicAccountantLei>
          <publicAccountantStateCountry publicAccountantState="US-NY" publicAccountantCountry="US"/>
        </publicAccountant>
      </publicAccountants>
      <isPublicAccountantChanged>N</isPublicAccountantChanged>
      <isOpinionOffered>N</isOpinionOffered>
      <isMaterialChange>N</isMaterialChange>
      <isAccountingPrincipleChange>N</isAccountingPrincipleChange>
    </registrantInfo>
    <unitInvestmentTrust>
      <depositors>
        <depositor>
          <depositorName>Security Life of Denver Insurance Company</depositorName>
          <depositorCrdNo>N/A</depositorCrdNo>
          <depositorLei>YOFNFTDEY0VHBO71S928</depositorLei>
          <depositorStateCountry depositorCountry="US" depositorState="US-CO"/>
          <depositorUltimateParentname>Voya Financial, Inc.</depositorUltimateParentname>
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      <uitAdmins>
        <uitAdmin>
          <uitAdminName>Security Life of Denver Insurance Company</uitAdminName>
          <uitAdminLei>YOFNFTDEY0VHBO71S928</uitAdminLei>
          <uitAdminStateCountry uitAdminCountry="US" uitAdminState="US-CO"/>
          <isUitAdminAffiliated>Y</isUitAdminAffiliated>
          <isUitAdminSubAdmin>N</isUitAdminSubAdmin>
        </uitAdmin>
      </uitAdmins>
      <isUitAdminHiredTerminated>N</isUitAdminHiredTerminated>
      <registrantSeparateInsuranceAccount isRegistrantSeparateInsuranceAccount="Y" separateAccountSeriesId="S000000025"/>
      <numOfContracts>12126</numOfContracts>
      <contractSecurities>
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        <contractSecurity grossPremiumReceivedSection1035="1225992" separateAccountSecurityName="Voya SVUL-CV" contractValueRedeemed="1288546" numContractsSold="2" grossPremiumReceived="3572245" separateAccountTotalAsset="39389883" separateAccountContractId="C000070763" numContractsAffected="2" numContractsAffectedRedeemed="0" contractValueRedeemedSection1035="0"/>
        <contractSecurity grossPremiumReceivedSection1035="28956" separateAccountSecurityName="Voya VUL-CV" contractValueRedeemed="18581428" numContractsSold="9" grossPremiumReceived="15081674" separateAccountTotalAsset="150315720" separateAccountContractId="C000058266" numContractsAffected="3" numContractsAffectedRedeemed="42" contractValueRedeemedSection1035="3752929"/>
        <contractSecurity grossPremiumReceivedSection1035="29551" separateAccountSecurityName="Voya VUL-DB" contractValueRedeemed="2222294" numContractsSold="33" grossPremiumReceived="3235571" separateAccountTotalAsset="14656200" separateAccountContractId="C000092411" numContractsAffected="1" numContractsAffectedRedeemed="4" contractValueRedeemedSection1035="87167"/>
        <contractSecurity grossPremiumReceivedSection1035="0" separateAccountSecurityName="Asset Accumulator" contractValueRedeemed="12268268" numContractsSold="0" grossPremiumReceived="3356923" separateAccountTotalAsset="84139887" separateAccountContractId="C000003989" numContractsAffected="0" numContractsAffectedRedeemed="40" contractValueRedeemedSection1035="4533638"/>
        <contractSecurity grossPremiumReceivedSection1035="0" separateAccountSecurityName="Asset Portfolio Manager" contractValueRedeemed="23203572" numContractsSold="0" grossPremiumReceived="9796994" separateAccountTotalAsset="189477424" separateAccountContractId="C000000038" numContractsAffected="0" numContractsAffectedRedeemed="38" contractValueRedeemedSection1035="4191591"/>
        <contractSecurity grossPremiumReceivedSection1035="0" separateAccountSecurityName="Corporate Benefits" contractValueRedeemed="4687309" numContractsSold="0" grossPremiumReceived="1262638" separateAccountTotalAsset="39977265" separateAccountContractId="C000000039" numContractsAffected="0" numContractsAffectedRedeemed="12" contractValueRedeemedSection1035="1764312"/>
        <contractSecurity grossPremiumReceivedSection1035="0" separateAccountSecurityName="Estate Designer" contractValueRedeemed="6238453" numContractsSold="0" grossPremiumReceived="591825" separateAccountTotalAsset="58054765" separateAccountContractId="C000000040" numContractsAffected="0" numContractsAffectedRedeemed="2" contractValueRedeemedSection1035="1529518"/>
        <contractSecurity grossPremiumReceivedSection1035="0" separateAccountSecurityName="FirstLine" contractValueRedeemed="18199074" numContractsSold="0" grossPremiumReceived="4139647" separateAccountTotalAsset="193687197" separateAccountContractId="C000000041" numContractsAffected="0" numContractsAffectedRedeemed="10" contractValueRedeemedSection1035="2028420"/>
        <contractSecurity grossPremiumReceivedSection1035="0" separateAccountSecurityName="FirstLine II" contractValueRedeemed="18716468" numContractsSold="0" grossPremiumReceived="9666686" separateAccountTotalAsset="106237637" separateAccountContractId="C000062869" numContractsAffected="0" numContractsAffectedRedeemed="11" contractValueRedeemedSection1035="590550"/>
        <contractSecurity grossPremiumReceivedSection1035="0" separateAccountSecurityName="Strategic Advantage" contractValueRedeemed="20066037" numContractsSold="0" grossPremiumReceived="2096206" separateAccountTotalAsset="113073880" separateAccountContractId="C000003990" numContractsAffected="0" numContractsAffectedRedeemed="33" contractValueRedeemedSection1035="7264561"/>
        <contractSecurity grossPremiumReceivedSection1035="0" separateAccountSecurityName="Strategic Investor" contractValueRedeemed="15352310" numContractsSold="0" grossPremiumReceived="4236232" separateAccountTotalAsset="95145225" separateAccountContractId="C000000042" numContractsAffected="0" numContractsAffectedRedeemed="12" contractValueRedeemedSection1035="1988692"/>
        <contractSecurity grossPremiumReceivedSection1035="0" separateAccountSecurityName="Variable Survivorship" contractValueRedeemed="16463578" numContractsSold="0" grossPremiumReceived="6196725" separateAccountTotalAsset="199887927" separateAccountContractId="C000000043" numContractsAffected="0" numContractsAffectedRedeemed="11" contractValueRedeemedSection1035="3179399"/>
        <contractSecurity grossPremiumReceivedSection1035="0" separateAccountSecurityName="Voya VUL-ECV" contractValueRedeemed="843474" numContractsSold="0" grossPremiumReceived="323499" separateAccountTotalAsset="5451285" separateAccountContractId="C000064577" numContractsAffected="0" numContractsAffectedRedeemed="10" contractValueRedeemedSection1035="268001"/>
        <contractSecurity grossPremiumReceivedSection1035="0" separateAccountSecurityName="Voya Corporate Advantage" contractValueRedeemed="0" numContractsSold="0" grossPremiumReceived="83097" separateAccountTotalAsset="1896080" separateAccountContractId="C000003988" numContractsAffected="0" numContractsAffectedRedeemed="0" contractValueRedeemedSection1035="0"/>
      </contractSecurities>
      <isRule6C7Reliance>N</isRule6C7Reliance>
      <isRule11A2Reliance>N</isRule11A2Reliance>
    </unitInvestmentTrust>
    <attachmentsTab>
      <isLegalProceedings>false</isLegalProceedings>
      <isProvisionFinancialSupport>false</isProvisionFinancialSupport>
      <isIPAReportInternalControl>false</isIPAReportInternalControl>
      <isChangeAccPrinciples>false</isChangeAccPrinciples>
      <isInfoRequiredEO>false</isInfoRequiredEO>
      <isOtherInfoRequired>false</isOtherInfoRequired>
    </attachmentsTab>
    <signature registrantSignedName="SECURITY LIFE SEPARATE ACCOUNT L1" signature="Wayne Forlines" title="Vice President" signedDate="2020-03-12"/>
  </formData>
</edgarSubmission>
