Exhibit 5.2
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                           [Ropes & Gray Letterhead]


                              August 4, 2000



Boston Life Sciences, Inc.
137 Newbury Street
Boston, Massachusetts 02116

     Re:  Boston Life Sciences, Inc.

Ladies and Gentlemen:

This opinion is furnished to you in connection with amendment no. 1 to a
registration statement on Form S-3 (the "Registration Statement"), filed today
with the Securities and Exchange Commission under the Securities Act of 1933, as
amended, for the registration of (i) 43,000 shares of the Common Stock, $.01 par
value, of Boston Life Sciences, Inc., a Delaware corporation (the "Company"),
issuable upon the exercise of Warrants No. BLSI-J-152 to purchase 8,000 shares
of the Company's Common Stock and Warrants No. BLSI-J-153 to purchase 35,000
shares of the Company's Common Stock, (ii) 173,000 shares of the Company's
Common Stock issuable upon the exercise of Warrants No. BLSI-J-148 to purchase
173,000 shares of the Company's Common Stock, (iii) 55,000 shares of the
Company's Common Stock issuable upon the exercise of Warrants No. BLSI-J-149 to
purchase 55,000 shares of the Company's Common Stock, (iv) 9,500 shares of the
Company's Common Stock issuable upon the exercise of Warrants No. BLSI-J-150 to
purchase 9,500 shares of the Company's Common Stock and (v) 9,500 shares of the
Company's Common Stock issuable upon the exercise of Warrants No. BLSI-J-151 to
purchase 9,500 shares of the Company's Common Stock.  The foregoing Warrants are
referred to collectively herein as the "HCW Warrants," and the Common Stock
issuable upon exercise of the HCW Warrants is referred to collectively herein as
the "HCW Warrant Shares."

  The Company originally sold the HCW Warrants pursuant to an Engagement


Agreement (the "Engagement Agreement") dated September 14, 1999 between the
Company and H.C. Wainwright & Co., Inc. ("HCW").  Based upon instructions set
forth in a letter to the Company from HCW dated April 5, 2000 (the "HCW
Letter"), the Company issued certain of the HCW Warrants to HCW and certain of
the HCW Warrants to various employees of HCW.  We understand that the HCW
Warrant Shares are being registered to permit the secondary trading of such
Common Stock by the holders thereof from time to time after the effective date
of the Registration Statement.

     We have not acted as counsel for the Company in connection with either its
issuance and sale of the HCW Warrants or the preparation of the Engagement
Agreement or the HWC Letter.  For purposes of this opinion, we have examined and
relied upon such documents, records, certificates and other instruments as we
have deemed necessary.  We have examined one of the HCW Warrants furnished by
the Company to us, to wit, Warrants No. BLSI-J-148, and have assumed, based upon
a representation of the Company, that the other HCW Warrants are identical in
all respects to the HCW Warrant we examined (other than the number of underlying
HCW Warrant Shares, the name of the warrantholder and the warrant number).

     We express no opinion as to the applicability of, compliance with or effect
of Federal law or the law of any jurisdiction other than The Commonwealth of
Massachusetts and the corporate laws of the State of Delaware.

     Based on the foregoing, we are of the opinion that the HCW Warrant Shares
have been duly authorized and when the HCW Warrant Shares are issued out of the
Company's duly authorized Common Stock upon exercise of, and pursuant to the
provisions of, the HCW Warrants, the HCW Letter and the Engagement Agreement and
the Company has received the consideration therefor in accordance with the terms
of the HCW Warrants, the HCW Letter and the Engagement Agreement, the HCW
Warrant Shares will be validly issued, fully paid and non-assessable.

     We hereby consent to your filing this opinion as an exhibit to the
Registration Statement and to the use of our name therein and in the related
prospectus under the caption "Legal Matters".

     It is understood that this opinion is to be used only in connection with
the offer and sale of the HCW Warrant Shares while the Registration Statement is
in effect.

                              Very truly yours,



                              Ropes & Gray