<SUBMISSION>
<ACCESSION-NUMBER>0001179110-05-009438
<TYPE>3
<PUBLIC-DOCUMENT-COUNT>1
<PERIOD>20050511
<FILING-DATE>20050511
<DATE-OF-FILING-DATE-CHANGE>20050511
<ISSUER>
<COMPANY-DATA>
<CONFORMED-NAME>Warner Music Group Corp.
<CIK>0001319161
<ASSIGNED-SIC>7900
<IRS-NUMBER>134271875
<STATE-OF-INCORPORATION>DE
<FISCAL-YEAR-END>0930
</COMPANY-DATA>
<BUSINESS-ADDRESS>
<STREET1>75 ROCKEFELLER PLAZA
<CITY>NEW YORK
<STATE>NY
<ZIP>10019
<PHONE>212-275-2000
</BUSINESS-ADDRESS>
<MAIL-ADDRESS>
<STREET1>75 ROCKEFELLER PLAZA
<CITY>NEW YORK
<STATE>NY
<ZIP>10019
</MAIL-ADDRESS>
<FORMER-COMPANY>
<FORMER-CONFORMED-NAME>WMG Parent Corp.
<DATE-CHANGED>20050228
</FORMER-COMPANY>
</ISSUER>
<REPORTING-OWNER>
<OWNER-DATA>
<CONFORMED-NAME>LEE THOMAS H ADVISORS LLC
<CIK>0001260943
<STATE-OF-INCORPORATION>DE
<FISCAL-YEAR-END>1231
</OWNER-DATA>
<FILING-VALUES>
<FORM-TYPE>3
<ACT>34
<FILE-NUMBER>001-32502
<FILM-NUMBER>05819069
</FILING-VALUES>
<BUSINESS-ADDRESS>
<STREET1>C/O THOMAS H. LEE PARTNERS, L.P.
<STREET2>100 FEDERAL STREET, 35TH FLOOR
<CITY>BOSTON
<STATE>MA
<ZIP>02110
<PHONE>6172271050
</BUSINESS-ADDRESS>
<MAIL-ADDRESS>
<STREET1>C/O THOMAS H. LEE PARTNERS, L.P.
<STREET2>100 FEDERAL STREET, 35TH FLOOR
<CITY>BOSTON
<STATE>MA
<ZIP>02110
</MAIL-ADDRESS>
</REPORTING-OWNER>
<DOCUMENT>
<TYPE>3
<SEQUENCE>1
<FILENAME>edgar.xml
<DESCRIPTION>FORM 3 -
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>3</documentType>

    <periodOfReport>2005-05-11</periodOfReport>

    <noSecuritiesOwned>0</noSecuritiesOwned>

    <issuer>
        <issuerCik>0001319161</issuerCik>
        <issuerName>Warner Music Group Corp.</issuerName>
        <issuerTradingSymbol>WMG</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001260943</rptOwnerCik>
            <rptOwnerName>LEE THOMAS H ADVISORS LLC</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O THOMAS H. LEE PARTNERS, LP</rptOwnerStreet1>
            <rptOwnerStreet2>100 FEDERAL STREET, 35TH FLOOR</rptOwnerStreet2>
            <rptOwnerCity>BOSTON</rptOwnerCity>
            <rptOwnerState>MA</rptOwnerState>
            <rptOwnerZipCode>02110</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle></officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>55491627.88</value>
                    <footnoteId id="F1"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>See Note</value>
                    <footnoteId id="F2"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">Represents shares of the Issuer held directly by Thomas H. Lee Equity Fund V, L.P., Thomas H. Lee Parallel Fund V, L.P., Thomas H. Lee Equity (Cayman) Fund V, L.P., and THL WMG Equity Investors, L.P. (collectively, the &quot;Funds&quot;).</footnote>
        <footnote id="F2">The reporting person is the general partner of Thomas H. Lee Partners, L.P., which is the manager of THL Equity Advisors V, LLC, which, in turn, is the general partner of each of the Funds.  As such, the reporting person may be deemed to beneficially own the shares of the Issuer owned directly by each of the Funds.  The reporting person disclaims beneficial ownership of such shares, and this report shall not be deemed an admission that the reporting person is the beneficial owner of the securities for the purpose of Section 16 or for any other purpose, except to the extent of his pecuniary interest therein.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ Scott M. Sperling</signatureName>
        <signatureDate>2005-05-11</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SUBMISSION>
