Exhibit 32

I, Peter T. Kissinger, the Chairman of the Board; President; and Chief Executive Officer of Bioanalytical Systems, Inc., certify that (i) the Annual Report on Form 10-K for the year ended September 30, 2003, (the “Report”) fully complies with the requirements of Section 13(a) or 15(d) of the Securities Exchange Act of 1934, and (ii) the information contained in the Report fairly presents, in all material respects, the financial condition and results of operations of Bioanalytical Systems, Inc. as of the dates and for the periods set forth therein.

/s/  Peter T. Kissinger Peter T. Kissinger
Chairman of the Board
President and
Chief Executive Officer
January 13, 2004

I, Michael P. Silvon, the interim Chief Financial Officer and Vice President Planning and Development of Bioanalytical Systems, Inc., certify that (i) the Annual Report on Form 10-K for the year ended September 30, 2003, (the “Report”) fully complies with the requirements of Section 13(a) or 15(d) of the Securities Exchange Act of 1934, and (ii) the information contained in the Report fairly presents, in all material respects, the financial condition and results of operations of Bioanalytical Systems, Inc. as of the dates and for the periods set forth therein.

/s/  Michael P. Silvon Michael P. Silvon
Chief Financial Officer (Interim)
Vice President, Planning & Development
January 13, 2004