Aspen Technology 10-Q 2004 Q2 Quarterly report

EXHIBIT 32.2

CERTIFICATION PURSUANT TO RULE 13a-14(b) OR RULE 15d-14(b)
OF THE SECURITIES EXCHANGE ACT OF 1934 AND 18 U.S.C. SECTION 1350,
AS ADOPTED PURSUANT TO
SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002

In connection with the Quarterly Report on Form 10-Q of Aspen Technology, Inc. (the “Company”) for the period ended December 31, 2003 as filed with the Securities and Exchange Commission on the date hereof (the “Report”), the undersigned, Charles F. Kane, Senior Vice President and Chief Financial Officer of the Company hereby certifies, pursuant to 18 U.S.C. Section 1350, that:

1.The Report fully complies with the requirements of Section 13(a) or 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.

Dated: February 17, 2004
	/s/ CHARLES F. KANE
	Charles F. Kane
	Senior Vice President and Chief Financial Officer