<SUBMISSION>
<ACCESSION-NUMBER>0001104659-09-066611
<TYPE>4
<PUBLIC-DOCUMENT-COUNT>1
<PERIOD>20091119
<FILING-DATE>20091123
<DATE-OF-FILING-DATE-CHANGE>20091123
<REPORTING-OWNER>
<OWNER-DATA>
<CONFORMED-NAME>Malone Evan Daniel
<CIK>0001442645
</OWNER-DATA>
<FILING-VALUES>
<FORM-TYPE>4
<ACT>34
<FILE-NUMBER>001-33982
<FILM-NUMBER>091203058
</FILING-VALUES>
<MAIL-ADDRESS>
<STREET1>2319 LOCUST STREET
<CITY>PHILADELPHIA
<STATE>PA
<ZIP>19103
</MAIL-ADDRESS>
</REPORTING-OWNER>
<ISSUER>
<COMPANY-DATA>
<CONFORMED-NAME>LIBERTY MEDIA CORP
<CIK>0001355096
<ASSIGNED-SIC>4841
<IRS-NUMBER>841288730
<FISCAL-YEAR-END>1231
</COMPANY-DATA>
<BUSINESS-ADDRESS>
<STREET1>12300 LIBERTY BOULEVARD
<CITY>ENGLEWOOD
<STATE>CO
<ZIP>80112
<PHONE>7208755400
</BUSINESS-ADDRESS>
<MAIL-ADDRESS>
<STREET1>12300 LIBERTY BOULEVARD
<CITY>ENGLEWOOD
<STATE>CO
<ZIP>80112
</MAIL-ADDRESS>
<FORMER-COMPANY>
<FORMER-CONFORMED-NAME>Liberty Media Holding CORP
<DATE-CHANGED>20060303
</FORMER-COMPANY>
</ISSUER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>a4.xml
<DESCRIPTION>4
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0303</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2009-11-19</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001355096</issuerCik>
        <issuerName>LIBERTY MEDIA CORP</issuerName>
        <issuerTradingSymbol>LMDI (1)</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001442645</rptOwnerCik>
            <rptOwnerName>Malone Evan Daniel</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>2319 LOCUST STREET</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>PHILADELPHIA</rptOwnerCity>
            <rptOwnerState>PA</rptOwnerState>
            <rptOwnerZipCode>19103</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Series A Liberty Entertainment common stock</value>
                <footnoteId id="F1"/>
            </securityTitle>
            <transactionDate>
                <value>2009-11-19</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>J</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F2"/>
                <footnoteId id="F3"/>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>676</value>
                </transactionShares>
                <transactionPricePerShare>
                    <footnoteId id="F2"/>
                    <footnoteId id="F3"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>75</value>
                    <footnoteId id="F1"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">Immediately following the Split-Off (as defined below), Liberty Entertainment common stock (LMDI) was redesignated as Liberty Starz common stock (LSTZ).</footnote>
        <footnote id="F2">On November 19, 2009, the Issuer completed a partial redemption of Liberty Entertainment common stock (the Split-Off),  pursuant to which 0.9 of each share of the Issuer's Liberty Entertainment common stock was redeemed for 0.9 of a share of the corresponding series of the common stock of a newly formed, wholly owned subsidiary of the Issuer, Liberty Entertainment, Inc. (LEI), with 0.1 of each share of Liberty Entertainment common stock remaining outstanding and redesignated as Liberty Starz common stock.</footnote>
        <footnote id="F3">Immediately following the Split-Off on November 19, 2009,  a business combination transaction (the DTV Business Combination) among the Issuer, LEI, The DIRECTV, Group, Inc. (DIRECTV) , DIRECTV (Holdings) and certain other persons was completed.  Pursuant to the DTV Business Combination, (i) John Malone and certain related persons contributed each of their shares of LEI Series B common stock to Holdings for 1.11130 shares of Holdings Class B common stock, (ii) LEI merged with a subsidiary of Holdings and each share of LEI Series A common stock and Series B common stock outstanding at such time was converted into 1.11130 shares of Holdings Class A common stock; and (iii) DIRECTV merged with a subsidiary of Holdings and each share of DIRECTV common stock was converted into one share of Holdings Class A common stock.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>By: /s/ Evan D. Malone</signatureName>
        <signatureDate>2009-11-23</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SUBMISSION>
