Exhibit 5

PERKINS, SMITH & COHEN, LLP
--------------------------------------------------------------------------------
                                              Attorneys At Law

                                              ONE BEACON STREET
                                              BOSTON, MA 02108-3106
                                              TEL 617.854.4000  FAX 617.854.4040
                                              www.pscboston.com


                                                   December 5, 2001

Pro-Pharmaceuticals, Inc.
189 Wells Avenue, Suite 200
Newton, Massachusetts 02458

Ladies and Gentlemen:

     We have acted as special counsel for Pro-Pharmaceuticals, Inc., a Nevada
corporation (the "Company"), in connection with the preparation and filing with
the Securities and Exchange Commission (the "Commission") under the Securities
Act of 1933, as amended (the "Securities Act"), of a Registration Statement on
Form SB-2 (the "Registration Statement"), including a prospectus to be filed
with the Commission pursuant to Rule 424(b) of Regulation C promulgated under
the Securities Act (the "Prospectus") relating to shares of the Company's common
stock, par value $.001 per share (the "Common Stock"), as follows: (i) a "best
efforts" placement of up to 1,428,572 shares of Common Stock to be issued and
sold by the Company (the "Company Shares"), and (ii) the offering of up to
1,221,890 shares of Common Stock by certain stockholders of the Company (the
"Stockholders' Shares").

     As special counsel to the Company, in connection with this opinion, we have
examined and relied upon such records, documents, certificates and other
instruments as in our judgment are necessary or appropriate to form the basis
for the opinions set forth herein. In our examinations, we have assumed the
genuineness of all signatures, the legal capacity of natural persons signing or
delivering any instrument, the authenticity of all documents submitted to us as
originals, the conformity to original documents of all documents submitted to us
as certified or photostatic copies and the authenticity of the originals of such
latter documents.

     Based upon the foregoing, we are of the opinion that:

     1. The Company Shares, when issued and sold in accordance with the
Registration Statement and related Prospectus, will be validly issued, fully
paid and non-assessable.

     2. The Stockholders' Shares have been duly authorized and validly issued
and are fully paid and non-assessable.




                                                     PERKINS, SMITH & COHEN, LLP
Pro-Pharmaceuticals, Inc.
December 5, 2001
Page 2


     We hereby consent to the filing of this opinion as an exhibit to the
Registration Statement and to the reference to this firm appearing under the
heading "Legal Matters" in the Prospectus. In giving such consent, we do not
thereby admit that we are in the category of persons whose consent is required
under Section 7 of the Securities Act or the General Rules and Regulations of
the Commission thereunder.

                                         Very truly yours,

                                         /s/ Perkins, Smith & Cohen, LLP

                                         Perkins, Smith & Cohen, LLP