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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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MIC-Info: RSA-MD5,RSA,
 IDmHfYHUj5cIAgKA3U67zLtPXtuo141VJypCwxaNmfBB1wyrfrYttN7tAUXYOPzA
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<SEC-DOCUMENT>0000069499-03-000046.txt : 20030814
<SEC-HEADER>0000069499-03-000046.hdr.sgml : 20030814
<ACCEPTANCE-DATETIME>20030814161600
ACCESSION NUMBER:		0000069499-03-000046
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20030813
FILED AS OF DATE:		20030814

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			SUNSERI PATRICIA
		CENTRAL INDEX KEY:			0001051093

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-09114
		FILM NUMBER:		03847948

	BUSINESS ADDRESS:	
		STREET 1:		C/O 1030 CENTURY BUILDING
		STREET 2:		130 SEVENTH STREET
		CITY:			PITTSBURGH
		STATE:			PA
		ZIP:			15222

	MAIL ADDRESS:	
		STREET 1:		MYLAN LABORATORIES INC
		STREET 2:		130 SEVENTH STREET
		CITY:			PITTSBURGH
		STATE:			PA
		ZIP:			15222

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			MYLAN LABORATORIES INC
		CENTRAL INDEX KEY:			0000069499
		STANDARD INDUSTRIAL CLASSIFICATION:	PHARMACEUTICAL PREPARATIONS [2834]
		IRS NUMBER:				251211621
		STATE OF INCORPORATION:			PA
		FISCAL YEAR END:			0331

	BUSINESS ADDRESS:	
		STREET 1:		1500 CORPORATE DRIVE
		STREET 2:		SUITE 400
		CITY:			CANONSBURG
		STATE:			PA
		ZIP:			15317
		BUSINESS PHONE:		724-514-1800

	MAIL ADDRESS:	
		STREET 1:		1500 CORPORATE DRIVE
		STREET 2:		SUITE 400
		CITY:			CANONSBURG
		STATE:			PA
		ZIP:			15317

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	FRM CORP
		DATE OF NAME CHANGE:	19711003
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>primary_doc.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>

<ownershipDocument>

    <schemaVersion>X0201</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2003-08-13</periodOfReport>


    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000069499</issuerCik>
        <issuerName>MYLAN LABORATORIES INC</issuerName>
        <issuerTradingSymbol>MYL</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001051093</rptOwnerCik>
            <rptOwnerName>SUNSERI PATRICIA</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>MYLAN LABORATORIES INC</rptOwnerStreet1>
            <rptOwnerStreet2>1500 CORPORATE DR  SUITE 400</rptOwnerStreet2>
            <rptOwnerCity>CANONSBURG</rptOwnerCity>
            <rptOwnerState>PA</rptOwnerState>
            <rptOwnerZipCode>15317</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Senior VP, Mylan Laboratories</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>

        <nonDerivativeTransaction>
            <securityTitle>
                <value>Mylan Laboratories Inc. Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2003-08-13</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>100000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>34.3942</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>507124</value>
                    <footnoteId id="F1"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>

    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">Mylan Laboratories Inc. common stock Indirect ownership through 401(k) holdings was 5,807 as of August 8, 2003.</footnote>
    </footnotes>


    <ownerSignature>
        <signatureName>Particia A. Sunseri</signatureName>
        <signatureDate>2003-08-14</signatureDate>
    </ownerSignature>

</ownershipDocument>

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