<SUBMISSION>
<ACCESSION-NUMBER>0000920148-03-000176
<TYPE>4
<PUBLIC-DOCUMENT-COUNT>1
<PERIOD>20031030
<FILING-DATE>20031103
<REPORTING-OWNER>
<OWNER-DATA>
<CONFORMED-NAME>LAI GOLDMAN MYLA
<CIK>0001168581
</OWNER-DATA>
<FILING-VALUES>
<FORM-TYPE>4
<ACT>34
<FILE-NUMBER>001-11353
<FILM-NUMBER>03973319
</FILING-VALUES>
<BUSINESS-ADDRESS>
<STREET1>430 S SPRING STREET
<CITY>BURLINGTON
<STATE>NC
<ZIP>27215
</BUSINESS-ADDRESS>
</REPORTING-OWNER>
<ISSUER>
<COMPANY-DATA>
<CONFORMED-NAME>LABORATORY CORP OF AMERICA HOLDINGS
<CIK>0000920148
<ASSIGNED-SIC>8071
<IRS-NUMBER>133757370
<STATE-OF-INCORPORATION>DE
<FISCAL-YEAR-END>1231
</COMPANY-DATA>
<BUSINESS-ADDRESS>
<STREET1>358 S MAIN ST
<CITY>BURLINGTON
<STATE>NC
<ZIP>27215
<PHONE>3362291127
</BUSINESS-ADDRESS>
<MAIL-ADDRESS>
<STREET1>358 S MAIN ST
<CITY>BURLINGTON
<STATE>NC
<ZIP>27215
</MAIL-ADDRESS>
<FORMER-COMPANY>
<FORMER-CONFORMED-NAME>NATIONAL HEALTH LABORATORIES HOLDINGS INC
<DATE-CHANGED>19940314
</FORMER-COMPANY>
</ISSUER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>primary_doc.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
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                <value></value>
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    </nonDerivativeTable>

    <derivativeTable>

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            <securityTitle>
                <value>Non-qualified Stock Options</value>
                <footnoteId id="F4"/>
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            <conversionOrExercisePrice>
                <value>10.3125</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2003-10-30</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>M</transactionCode>
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            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>14800</value>
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                <transactionPricePerShare>
                    <value>10.3125</value>
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                <transactionAcquiredDisposedCode>
                    <value>D</value>
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            <exerciseDate>
                <value>2003-02-09</value>
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            <expirationDate>
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                <underlyingSecurityTitle>
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    </derivativeTable>

    <footnotes>
        <footnote id="F1">Pursuant to a plan in compliance with Rule 10b5-1 under the Securities Exchange Act of 1934.</footnote>
        <footnote id="F2">Amount shown reflects a 2-for-1 stock split effective on May 10, 2002.</footnote>
        <footnote id="F3">Includes 2,000 shares of Common Stock held in Dr. Lai-Godlman's daughter's name. Dr. Lai-Goldman disclaims beneficial ownership of these shares.</footnote>
        <footnote id="F4">Common Stock purchase option granted under the Laboratory Corporation of America Holdings 1994 Stock Option Plan.</footnote>
    </footnotes>


    <ownerSignature>
        <signatureName>/s/ Bradford T. Smith, Attorney-In-Fact for Myla Lai-Goldman</signatureName>
        <signatureDate>2003-11-03</signatureDate>
    </ownerSignature>

</ownershipDocument>

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</TEXT>
</DOCUMENT>
</SUBMISSION>
