AptarGroup (ATR) 10-K 2009 FY Annual report

Exhibit 32.1

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

I, Peter H. Pfeiffer, the president and chief executive officer of AptarGroup, Inc., certify that (i) the Annual Report onForm 10-K of AptarGroup, Inc. for the year ended December 31, 2009 (the“Form 10-K”) 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 theForm 10-K fairly presents, in all material respects, the financial condition and results of operations of AptarGroup, Inc.

/s/  Peter H. Pfeiffer

Peter H. Pfeiffer

President and Chief Executive Officer

February 26, 2010