Exhibit 32.1

                                  CERTIFICATION
            PURSUANT TO SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002
(SUBSECTIONS (a) AND (b) OF SECTION 1350, CHAPTER 63 OF TITLE 18, UNITED STATES
                                      CODE)

Pursuant to section 906 of the Sarbanes-Oxley Act of 2002 (subsections (a) and
(b) of section 1350, chapter 63 of title 18, United States Code), each of the
undersigned officers of ARIAD Pharmaceuticals, Inc., a Delaware corporation (the
"Company"), does hereby certify, to such officer's knowledge, that:

The Quarterly Report on Form 10-Q for the quarter ended September 30, 2003 (the
"Form 10-Q") of the Company fully complies with the requirements of section
13(a) or 15(d) of the Securities Exchange Act of 1934, and information contained
in the Form 10-Q fairly presents, in all material respects, the financial
condition and results of operations of the Company.

Date: November 4, 2003                      /s/ Harvey J. Berger, M.D
                                            ------------------------------------
                                            Harvey J. Berger, M.D.
                                            Chairman and Chief Executive Officer

Date: November 4, 2003                      /s/ Edward M.Fitzgerald
                                            ------------------------------------
                                            Edward M. Fitzgerald
                                            Senior Vice President and Chief
                                            Financial Officer

A signed original of this written statement required by Section 906 has been
provided to the Company and will be retained by the Company and furnished to the
Securities and Exchange Commission or its staff upon request.

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