Exhibit 32.1

                            CERTIFICATION PURSUANT TO
                             18 U.S.C. SECTION 1350
                               ADOPTED PURSUANT TO
                  SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002

In connection with the Annual Report of Aceto Corporation, a New York
corporation (the "Company"), on Form 10-K for the period ended June 30, 2006 as
filed with the Securities and Exchange Commission on the date hereof (the
"Report"), I, Leonard S. Schwartz, Chairman, President and Chief Executive
Officer of the Company, certify, pursuant to Section 18 U.S.C. 1350, as adopted
pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, that:

        (1)     The Report fully complies with the requirements of Section 13(a)
                and 15(d) of the Securities Exchange Act of 1934; and

        (2)     The information contained in the Report fairly presents, in all
                material respects, the financial condition and results of
                operations of the Company.






/s/ Leonard S. Schwartz
- -----------------------
    Chairman, President and Chief Executive Officer
    September 7, 2006

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