<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0206</schemaVersion>

    <documentType>3</documentType>

    <periodOfReport>2009-11-24</periodOfReport>

    <noSecuritiesOwned>0</noSecuritiesOwned>

    <issuer>
        <issuerCik>0001392091</issuerCik>
        <issuerName>Blueknight Energy Partners, L.P.</issuerName>
        <issuerTradingSymbol>BKEP</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001684386</rptOwnerCik>
            <rptOwnerName>Blueknight Energy Holding, Inc.</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>2925 RICHMOND AVENUE, 11TH FLOOR</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>HOUSTON</rptOwnerCity>
            <rptOwnerState>TX</rptOwnerState>
            <rptOwnerZipCode>77098</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>1</isOther>
            <officerTitle></officerTitle>
            <otherText>Director by Deputization</otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001684640</rptOwnerCik>
            <rptOwnerName>Vitol Refining Group B.V.</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>2925 RICHMOND AVENUE, 11TH FLOOR</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>HOUSTON</rptOwnerCity>
            <rptOwnerState>TX</rptOwnerState>
            <rptOwnerZipCode>77098</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>1</isOther>
            <officerTitle></officerTitle>
            <otherText>Director by Deputization</otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001546531</rptOwnerCik>
            <rptOwnerName>Vitol Holding B.V.</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>2925 RICHMOND AVENUE, 11TH FLOOR</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>HOUSTON</rptOwnerCity>
            <rptOwnerState>TX</rptOwnerState>
            <rptOwnerZipCode>77098</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>1</isOther>
            <officerTitle></officerTitle>
            <otherText>Director by Deputization</otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001684862</rptOwnerCik>
            <rptOwnerName>Vitol Holding II S.A.</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>2925 RICHMOND AVENUE, 11TH FLOOR</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>HOUSTON</rptOwnerCity>
            <rptOwnerState>TX</rptOwnerState>
            <rptOwnerZipCode>77098</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>1</isOther>
            <officerTitle></officerTitle>
            <otherText>Director by Deputization</otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable></nonDerivativeTable>

    <derivativeTable>
        <derivativeHolding>
            <securityTitle>
                <value>Subordinated Units</value>
                <footnoteId id="F1"/>
            </securityTitle>
            <conversionOrExercisePrice>
                <footnoteId id="F1"/>
            </conversionOrExercisePrice>
            <exerciseDate>
                <footnoteId id="F1"/>
            </exerciseDate>
            <expirationDate>
                <footnoteId id="F1"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Units</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>12570504</value>
                    <footnoteId id="F1"/>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                    <footnoteId id="F2"/>
                    <footnoteId id="F3"/>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeHolding>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">As of November 24, 2009, the Subordinated Units had no expiration date and were convertible on a one-for-one basis into Common Units representing limited partner interests of Blueknight Energy Partners, L.P. (the &quot;Issuer&quot;) at the end of the subordination period, as set forth in the Issuer's First Amended and Restated Agreement of Limited Partnership, dated as of July 20, 2007, filed with the Securities and Exchange Commission as Exhibit 3.1 to the Issuer's Current Report on Form 8-K, filed on July 25, 2007. Because the subordinated units were acquired in connection with a transaction having the purpose or effect of changing or influencing the control of the Issuer, Blueknight Energy Holding, Inc. (&quot;Vitol Holding&quot;) may be deemed to have been the beneficial owner of the Common Units which would have been issuable upon conversion of the subordinated units pursuant to Rule 13d-3(d)(1)(i) of the Exchange Act.</footnote>
        <footnote id="F2">As of November 24, 2009, these securities were owned directly by Vitol Holding. This form is jointly filed by Vitol Holding, Vitol Refining Group B.V. (&quot;Refining&quot;), Vitol Holding B.V. (&quot;Holding&quot;), and Vitol Holding II, S.A. (&quot;Holding II&quot;).  Vitol Holding is wholly owned by Refining, which is wholly owned by Holding, which is wholly owned by Holding II.</footnote>
        <footnote id="F3">Accordingly, each of Vitol Holding, Refining, Holding and Holding II may be deemed to share voting and dispositive power over the reported securities, and as a result may also be deemed to be the beneficial owners of these securities. Each of Refining, Holding and Holding II disclaims beneficial ownership of these securities except to the extent of its pecuniary interest therein, and, pursuant to Rule 16a-1(a)(4) under the Securities Exchange Act of 1934, each of Refining, Holding and Holding II states that the inclusion of these securities in this report shall not be deemed an admission of beneficial ownership of all of the reported securities for purposes of Section 16 or for any other purpose.</footnote>
    </footnotes>

    <remarks>As the sole member of Blueknight Energy Partners G.P., L.L.C. (&quot;GP&quot;), the General Partner of the Issuer, as of November 24, 2009, Vitol Holding had the right to appoint all of the members of the board of directors of the GP. Therefore, Vitol Holding may be deemed a director by deputization.</remarks>

    <ownerSignature>
        <signatureName>/s/ Miguel A. Loya, Miguel A. Loya, President of Blueknight Energy Holding, Inc.</signatureName>
        <signatureDate>2016-09-27</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>/s/ Guy Richard Skern, Guy Richard Skern, Managing Director of Vitol Refining Group B.V.</signatureName>
        <signatureDate>2016-09-27</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>/s/ William Dennis Laneville, William Dennis Laneville, Managing Director of Vitol Holding B.V.</signatureName>
        <signatureDate>2016-09-27</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>/s/ Guy Richard Skern, Guy Richard Skern, Managing Director of Vitol Holding B.V.</signatureName>
        <signatureDate>2016-09-27</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>/s/ Jonathan Marsh, Jonathan Marsh, Director of Vitol Holding II, S.A.</signatureName>
        <signatureDate>2016-09-27</signatureDate>
    </ownerSignature>
</ownershipDocument>
