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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,
 KKpdZBXidZvNCpilUAFroqAS1/dBv/BtiX76GX1VOiBE48B8HuAI4/3PRKOm1l24
 kSYDwclDZS4Zj1+rLrrl+w==

<SEC-DOCUMENT>0001181431-03-014079.txt : 20030715
<SEC-HEADER>0001181431-03-014079.hdr.sgml : 20030715
<ACCEPTANCE-DATETIME>20030715152242
ACCESSION NUMBER:		0001181431-03-014079
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20030711
FILED AS OF DATE:		20030715

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			KELKER NORMAN E
		CENTRAL INDEX KEY:			0001251895

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-09974
		FILM NUMBER:		03787189

	MAIL ADDRESS:	
		STREET 1:		C/O ENZO BIOCHEM, INC.
		STREET 2:		60 EXECUTIVE BOULEVARD
		CITY:			FARMINGDALE
		STATE:			NY
		ZIP:			11735

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			ENZO BIOCHEM INC
		CENTRAL INDEX KEY:			0000316253
		STANDARD INDUSTRIAL CLASSIFICATION:	SERVICES-MEDICAL LABORATORIES [8071]
		IRS NUMBER:				132866202
		STATE OF INCORPORATION:			NY
		FISCAL YEAR END:			0731

	BUSINESS ADDRESS:	
		STREET 1:		60 EXECUTIVE BLVD
		CITY:			FARMINGDALE
		STATE:			NY
		ZIP:			11735
		BUSINESS PHONE:		5167555500

	MAIL ADDRESS:	
		STREET 1:		ENZO BIOCHEM INC
		STREET 2:		60 EXECUTIVE BLVD
		CITY:			FARMINGDALE
		STATE:			NY
		ZIP:			11735
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>rrd13243.xml
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>
    <schemaVersion>X0101</schemaVersion>

    <documentType>4</documentType>
<periodOfReport>2003-07-11</periodOfReport>
<notSubjectToSection16>0</notSubjectToSection16>
    <issuer>
        <issuerCik>0000316253</issuerCik>
        <issuerName>ENZO BIOCHEM INC</issuerName>
        <issuerTradingSymbol>ENZ</issuerTradingSymbol></issuer>
<reportingOwner>
<reportingOwnerId>
            <rptOwnerCik>0001251895</rptOwnerCik>
            <rptOwnerName>KELKER NORMAN E</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>  </rptOwnerStreet1>
            <rptOwnerStreet2>  </rptOwnerStreet2>
            <rptOwnerCity>  </rptOwnerCity>
            <rptOwnerState>  </rptOwnerState>
            <rptOwnerZipCode>  </rptOwnerZipCode>
        </reportingOwnerAddress>
            <reportingOwnerRelationship>
<isDirector>0</isDirector>
<isOfficer>1</isOfficer>
<isTenPercentOwner>0</isTenPercentOwner>
<isOther>0</isOther>
<officerTitle>Senior Vice President</officerTitle>
<otherText></otherText></reportingOwnerRelationship></reportingOwner>
<nonDerivativeSecurity>
<securityTitle>
<value>Common Stock</value></securityTitle>
<transactionDate>
<value>2003-07-11</value></transactionDate>
<transactionCoding>
<transactionFormType>4</transactionFormType>
<transactionCode>S</transactionCode>
<equitySwapInvolved>0</equitySwapInvolved></transactionCoding>
<transactionTimeliness>
<value></value></transactionTimeliness>
<transactionAmounts>
<transactionShares>
<value>1796</value></transactionShares>
<transactionValue>
<value>21.90</value></transactionValue>
<transactionAcquiredDisposedCode>
<value>D</value></transactionAcquiredDisposedCode></transactionAmounts>
<postTransactionAmounts>
<sharesOwnedFollowingTransaction>
<value>111990</value>
<footnoteId id="F1"/></sharesOwnedFollowingTransaction></postTransactionAmounts>
<ownershipNature>
<directOrIndirectOwnership>
<value>D</value></directOrIndirectOwnership>
<natureOfOwnership>
<value></value></natureOfOwnership></ownershipNature></nonDerivativeSecurity>
<nonDerivativeSecurity>
<securityTitle>
<value>Common Stock</value></securityTitle>
<transactionDate>
<value>2003-07-14</value></transactionDate>
<transactionCoding>
<transactionFormType>4</transactionFormType>
<transactionCode>S</transactionCode>
<equitySwapInvolved>0</equitySwapInvolved></transactionCoding>
<transactionTimeliness>
<value></value></transactionTimeliness>
<transactionAmounts>
<transactionShares>
<value>9500</value></transactionShares>
<transactionValue>
<value>21.9768</value></transactionValue>
<transactionAcquiredDisposedCode>
<value>D</value></transactionAcquiredDisposedCode></transactionAmounts>
<postTransactionAmounts>
<sharesOwnedFollowingTransaction>
<value>102490</value>
<footnoteId id="F2"/></sharesOwnedFollowingTransaction></postTransactionAmounts>
<ownershipNature>
<directOrIndirectOwnership>
<value>D</value></directOrIndirectOwnership>
<natureOfOwnership>
<value></value></natureOfOwnership></ownershipNature></nonDerivativeSecurity>
<derivativeSecurity>
<securityTitle>
<value>Stock Option (Right to buy)</value></securityTitle>
<conversionOrExercisePrice>
<value>13.50</value></conversionOrExercisePrice>
<transactionDate>
<value>2003-01-25</value></transactionDate>
<transactionCoding>
<transactionFormType>4</transactionFormType>
<transactionCode>A</transactionCode>
<equitySwapInvolved>0</equitySwapInvolved></transactionCoding>
<transactionAmounts>
<transactionShares>
<value>10000</value></transactionShares>
<transactionValue>
<value>0</value></transactionValue>
<transactionAcquiredDisposedCode>
<value>D</value></transactionAcquiredDisposedCode></transactionAmounts>
<exerciseDate>
<value>2003-01-25</value>
<footnoteId id="F3"/></exerciseDate>
<expirationDate>
<value>2013-01-25</value></expirationDate>
<underlyingSecurity>
<underlyingSecurityTitle>
<value>Common Stock</value></underlyingSecurityTitle>
<underlyingSecurityShares>
<value>10000</value></underlyingSecurityShares></underlyingSecurity>
<postTransactionAmounts>
<sharesOwnedFollowingTransaction>
<value>10000</value></sharesOwnedFollowingTransaction></postTransactionAmounts>
<ownershipNature>
<directOrIndirectOwnership>
<value>D</value></directOrIndirectOwnership>
<natureOfOwnership>
<value></value></natureOfOwnership></ownershipNature></derivativeSecurity>
<footnotes>
<footnote id="F1">Includes 2,427 shares held in ENZ&apos;s 401(k) plan, based on plan statement dated June 30, 2003.</footnote>
<footnote id="F2">Includes 2,427 shares held in ENZ&apos;s 401(k) plan, based on plan statement dated June 30, 2003.</footnote>
<footnote id="F3">Subject to 4 year vesting period beginning 1/25/03, vesting 25% per year.</footnote></footnotes>
<ownerSignature>
<signatureName>/s/ Norman E. Kelker</signatureName>
<signatureDate>2003-07-15</signatureDate></ownerSignature></ownershipDocument>


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