Exhibit 23.01



                         Consent of Independent Auditors


     We consent to the incorporation by reference in the Registration  Statement
pertaining  to the 1987  Stock  Option  Plan  (Form  S-8 No.  33-77060)  and the
Registration  Statement  pertaining  to the 1995 Stock Option Plan (Form S-8 No.
33-93048) of ATMI,  Inc. of our report dated February 11, 1998,  with respect to
the consolidated financial statements and schedule of ATMI, Inc. included in its
Annual Report (Form 10-K) for the year ended December 31, 1997.



                                                               Ernst & Young LLP
Stamford, Connecticut
March 19, 1998