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

    <schemaVersion>X0304</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2011-11-16</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001519632</issuerCik>
        <issuerName>LRR Energy, L.P.</issuerName>
        <issuerTradingSymbol>LRE</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001524901</rptOwnerCik>
            <rptOwnerName>Lime Rock Resources B, L.P.</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>HERITAGE PLAZA</rptOwnerStreet1>
            <rptOwnerStreet2>1111 BAGBY ST., STE. 4600</rptOwnerStreet2>
            <rptOwnerCity>HOUSTON</rptOwnerCity>
            <rptOwnerState>TX</rptOwnerState>
            <rptOwnerZipCode>77002</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>1</isOther>
            <otherText>Director by Deputization</otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common units representing limited partner interests</value>
            </securityTitle>
            <transactionDate>
                <value>2011-11-16</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>296082</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>19.00</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>296082</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Subordinated units representing limited partner interests</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>0</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2011-11-16</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>318368</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F2"/>
            </exerciseDate>
            <expirationDate>
                <footnoteId id="F2"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Units</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>318368</value>
                    <footnoteId id="F1"/>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>318368</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">Pursuant to the Purchase, Sale, Contribution, Conveyance and Assumption Agreement entered into by the Reporting Person, LRR Energy, L.P. (the &quot;Issuer&quot;) and the other parties thereto, the Reporting Person contributed certain assets to the Issuer and received in exchange for such contribution 296,082 common units and 318,368 subordinated units upon the closing of the Issuer's initial public offering on November 16, 2011.</footnote>
        <footnote id="F2">Each subordinated unit will convert into one common unit at the end of the subordination period described in the Issuer's Registration Statement on Form S-1 (No. 333-174017).  The subordinated units do not expire.</footnote>
    </footnotes>

    <remarks>The Reporting Person  is controlled indirectly by Jonathan C. Farber and John T. Reynolds. An affiliate of the Reporting Person, Lime Rock Management LP (&quot;LRM&quot;), has the right to appoint all of the directors to the Board of Directors (the &quot;Board&quot;) of LRE GP, LLC, the general partner of the Issuer.  Mr. Farber, in addition to the co-chief executive officers of the general partner of the Reporting Person, will serve on the Board as representatives of LRM.  Therefore, the Reporting Person may be deemed a director by deputization.</remarks>

    <ownerSignature>
        <signatureName>/s/ Kris Agarwal, as attorney-in-fact</signatureName>
        <signatureDate>2011-11-18</signatureDate>
    </ownerSignature>
</ownershipDocument>
