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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
Originator-Key-Asymmetric:
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 TWSM7vrzLADbmYQaionwg5sDW3P6oaM5D3tdezXMm7z1T+B+twIDAQAB
MIC-Info: RSA-MD5,RSA,
 GDmUnzmy8Cxr139g15WbpZGlNfvtjvgIXnx0deezUV8MjdMZJ+26Nae0fpBPPMia
 BLCwl+4NbMfKSzpATOxkBg==

<SEC-DOCUMENT>0000920148-04-000126.txt : 20040603
<SEC-HEADER>0000920148-04-000126.hdr.sgml : 20040603
<ACCEPTANCE-DATETIME>20040603163023
ACCESSION NUMBER:		0000920148-04-000126
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20040601
FILED AS OF DATE:		20040603

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			LANE WENDY E
		CENTRAL INDEX KEY:			0001200848

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-11353
		FILM NUMBER:		04847511

	BUSINESS ADDRESS:	
		STREET 1:		C/O LAB CORP
		STREET 2:		430 S SPRING ST
		CITY:			BURLINGTON
		STATE:			NC
		ZIP:			27215
		BUSINESS PHONE:		3364365066

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			LABORATORY CORP OF AMERICA HOLDINGS
		CENTRAL INDEX KEY:			0000920148
		STANDARD INDUSTRIAL CLASSIFICATION:	SERVICES-MEDICAL LABORATORIES [8071]
		IRS NUMBER:				133757370
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		358 S MAIN ST
		CITY:			BURLINGTON
		STATE:			NC
		ZIP:			27215
		BUSINESS PHONE:		3362291127

	MAIL ADDRESS:	
		STREET 1:		358 S MAIN ST
		CITY:			BURLINGTON
		STATE:			NC
		ZIP:			27215

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	NATIONAL HEALTH LABORATORIES HOLDINGS INC
		DATE OF NAME CHANGE:	19940314
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>primary_doc.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2004-06-01</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000920148</issuerCik>
        <issuerName>LABORATORY CORP OF AMERICA HOLDINGS</issuerName>
        <issuerTradingSymbol>LH</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001200848</rptOwnerCik>
            <rptOwnerName>LANE WENDY E</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1></rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity></rptOwnerCity>
            <rptOwnerState></rptOwnerState>
            <rptOwnerZipCode></rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2004-06-01</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>41</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>39.99</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>18533</value>
                    <footnoteId id="F2"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">Stock award represents half the monthly Director retainer pursuant to the Laboratory Corporation of America Holdings 1995 Stock Plan for Non-Employee Directors.</footnote>
        <footnote id="F2">Amount shown reflects a 2-for-1 stock split effective on May 10, 2002.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ Bradford T. Smith, Attorney-in-Fact for Wendy E. Lane</signatureName>
        <signatureDate>2004-06-03</signatureDate>
    </ownerSignature>
</ownershipDocument>

</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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