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                                                                     Exhibit 5.1
                                                                     -----------
                                                                                

                   Mintz, Levin, Cohn, Ferris, Glovsky and Popeo, P.C.
 
                                  One Financial Center
 
                               Boston, Massachusetts 02111

701 Pennsylvania Avenue, N.W.                            Telephone: 617/542-6000
Washington, D.C. 20004                                   Fax: 617/542-2241
Telephone: 202/434-7300                                  www.mintz.com
Fax: 202/434-7400


                               February 12, 1999



CardioTech International, Inc.
78E Olympia Avenue
Woburn, Massachusetts 01801

Ladies and Gentlemen:


     We have acted as counsel to CardioTech International, Inc., a Massachusetts
corporation (the "Company"), in connection with the preparation and filing with
the Securities and Exchange Commission of a Registration Statement on Form S-3
(the "Registration Statement"), pursuant to which the Company is registering
under the Securities Act of 1933, as amended, a total of 3,582,600 shares (the
"Shares") of its common stock, $.01 par value per share (the "Common Stock"),
for resale to the public.  The Shares are to be sold by the selling stockholders
identified in the Registration Statement.  This opinion is being rendered in
connection with the filing of the Registration Statement.  All capitalized terms
used herein and not otherwise defined shall have the respective meanings given
to them in the Registration Statement.

     In connection with this opinion, we have examined the Company's Restated
Articles of Organization and Amended and Restated By-Laws, both as currently in
effect, such other records of the corporate proceedings of the Company and
certificates of the Company's officers as we have deemed relevant, and the
Registration Statement and the exhibits thereto.

     In our examination, we have assumed the genuineness of all signatures, the
legal capacity of natural persons, the authenticity of all documents submitted
to us as originals, the conformity to original documents of all documents
submitted to us as certified, photostatic or facsimile copies and the
authenticity of the originals of such copies.

     Based upon the foregoing, we are of the opinion that (i) the Shares have
been duly and validly authorized by the Company and (ii) the Shares, when issued
and sold, will be duly and validly issued, fully paid and non-assessable shares
of the Common Stock.

     Our opinion is limited to the General Corporation Laws of The Commonwealth
of Massachusetts, and we express no opinion with respect to the laws of any
other jurisdiction.  No opinion is expressed herein with respect to the
qualification of the Shares under the securities or blue sky laws of any state
or any foreign jurisdiction.

     We understand that you wish to file this opinion as an exhibit to the
Registration Statement, and we hereby consent thereto.



                                 Very truly yours,



                                 /s/ Mintz, Levin, Cohn, Ferris,
                                 Glovsky and Popeo, P.C.

                                 Mintz, Levin, Cohn, Ferris,
                                 Glovsky and Popeo, P.C.