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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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MIC-Info: RSA-MD5,RSA,
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 FD9Jz/M2tMYyA9AxUyVNFg==

<SEC-DOCUMENT>0001179110-05-013369.txt : 20050701
<SEC-HEADER>0001179110-05-013369.hdr.sgml : 20050701
<ACCEPTANCE-DATETIME>20050701114813
ACCESSION NUMBER:		0001179110-05-013369
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20050630
FILED AS OF DATE:		20050701
DATE AS OF CHANGE:		20050701

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			LIBERTY MEDIA CORP /DE/
		CENTRAL INDEX KEY:			0001082114
		STANDARD INDUSTRIAL CLASSIFICATION:	CABLE & OTHER PAY TELEVISION SERVICES [4841]
		IRS NUMBER:				841288730
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		12300 LIBERTY BLVD.
		CITY:			ENGLEWOOD
		STATE:			CO
		ZIP:			80112
		BUSINESS PHONE:		7208755400

	MAIL ADDRESS:	
		STREET 1:		12300 LIBERTY BLVD.
		CITY:			ENGLEWOOD
		STATE:			CO
		ZIP:			80112

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			ROMRELL LARRY E
		CENTRAL INDEX KEY:			0001120556

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-16615
		FILM NUMBER:		05931201

	BUSINESS ADDRESS:	
		STREET 1:		C/O LIBERTY MEDIA CORP
		STREET 2:		9197 SOUTH PEORIA STREET
		CITY:			ENGLEWOOD
		STATE:			CO
		ZIP:			80112
		BUSINESS PHONE:		8585999786

	MAIL ADDRESS:	
		STREET 1:		900 N SEWARD STREET
		CITY:			HOLLYWOOD
		STATE:			CA
		ZIP:			90038
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>edgar.xml
<DESCRIPTION>FORM 4 -
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2005-06-30</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001082114</issuerCik>
        <issuerName>LIBERTY MEDIA CORP /DE/</issuerName>
        <issuerTradingSymbol>L; LMC.B</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001120556</rptOwnerCik>
            <rptOwnerName>ROMRELL LARRY E</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>12300 LIBERTY BLVD.</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>ENGLEWOOD</rptOwnerCity>
            <rptOwnerState>CO</rptOwnerState>
            <rptOwnerZipCode>80112</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle></officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Series A Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2005-06-30</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>1226</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <footnoteId id="F1"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>221534</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">These shares of Series A common stock were received by the reporting person in payment of his director fees, which equaled $12,500, for the quarter ended June 30, 2005, in accordance with the terms of the Liberty Media Corporation 2002 Nonemployee Director Incentive Plan.  The number of shares was determined based upon the closing market price of the Series A common stock on June 30, 2005, which was $10.19 per share, with cash distributed in lieu of fractional shares.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ Larry E. Romrell</signatureName>
        <signatureDate>2005-07-01</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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