FORM 4
Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).
UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP OF SECURITIES

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934 or Section 30(h) of the Investment Company Act of 1940
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(Print or Type Responses)
1. Name and Address of Reporting Person *
THALENFELD BARBARA E
   2. Issuer Name and Ticker or Trading Symbol
ENZO BIOCHEM INC [ENZO] 		5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
_____ Director _____ 10% Owner
__X__ Officer (give title below) _____ Other (specify below)
VP, Corporate Development
(Last)
(First)
(Middle)
C/O ENZO BIOCHEM INC, 527 MADISON AVE		 3. Date of Earliest Transaction (Month/Day/Year)
08/10/2004
(Street)

NEW YORK, NY 10022		 4. If Amendment, Date Original Filed(Month/Day/Year)
08/16/2004		 6. Individual or Joint/Group Filing(Check Applicable Line)
_X_ Form filed by One Reporting Person
___ Form filed by More than One Reporting Person
(City)
(State)
(Zip)
Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1.Title of Security
(Instr. 3)		 2. Transaction Date (Month/Day/Year) 2A. Deemed Execution Date, if any (Month/Day/Year) 3. Transaction Code
(Instr. 8)		 4. Securities Acquired (A) or Disposed of (D)
(Instr. 3, 4 and 5)		 5. Amount of Securities Beneficially Owned Following Reported Transaction(s)
(Instr. 3 and 4)		 6. Ownership Form: Direct (D) or Indirect (I)
(Instr. 4)		 7. Nature of Indirect Beneficial Ownership
(Instr. 4)
Code V Amount (A) or (D) Price
Common Stock, par value $.01 per share 08/10/2004   M   3,350 A $ 7.276 53,117 (2) D  

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Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned
(e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security
(Instr. 3)		 2. Conversion or Exercise Price of Derivative Security 3. Transaction Date (Month/Day/Year) 3A. Deemed Execution Date, if any (Month/Day/Year) 4. Transaction Code
(Instr. 8)		 5. Number of Derivative Securities Acquired (A) or Disposed of (D)
(Instr. 3, 4, and 5)		 6. Date Exercisable and Expiration Date
(Month/Day/Year)		 7. Title and Amount of Underlying Securities
(Instr. 3 and 4)		 8. Price of Derivative Security
(Instr. 5)		 9. Number of Derivative Securities Beneficially Owned Following Reported Transaction(s)
(Instr. 4)		 10. Ownership Form of Derivative Security: Direct (D) or Indirect (I)
(Instr. 4)		 11. Nature of Indirect Beneficial Ownership
(Instr. 4)
Code V (A) (D) Date Exercisable Expiration Date Title Amount or Number of Shares
Incentive Stock Option $ 7.276 08/10/2004   M   3,350   08/17/1994(1) 08/16/2004(1) Common Stock 3,350 $ 0 53,117 (2) D  

Reporting Owners

Reporting Owner Name / Address Relationships
 Director  10% Owner  Officer  Other
THALENFELD BARBARA E
C/O ENZO BIOCHEM INC
527 MADISON AVE
NEW YORK, NY 10022		       VP, Corporate Development  

Signatures

 /s/Dr. Barbara E. Thalenfeld   08/13/2004
**Signature of Reporting Person Date

Explanation of Responses:

* If the form is filed by more than one reporting person, see Instruction 4(b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations. See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
(1) The options vested as to 25% of the shares on the one (1) year anniversary of the date of grant (8/17/94) and 25% on each one year anniversary thereafter.
(2) As of the date hereof, the Reporting Person directly beneficially owns 5,260 shares of Common Stock, 2,552 shares of Common Stock in Enzo Biochem's 401K plan and 45,505 options to purchase Common Stock, par value $.01 per share which are currently exercisable.

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