Aspen Technology Announces Date of Selected Preliminary Fiscal 2009 Third-Quarter Financial Results Release, Conference Call and Webcast

Burlington, Mass. - Aspen Technology, Inc. (OTC: AZPN.PK), a leading provider of software and services to the process industries, today announced that the company will release selected preliminary financial results for its third quarter fiscal 2009, ended March 31, 2009, before the U.S. financial markets open on Friday, May 15, 2009.

In conjunction with this announcement, AspenTech will host a conference call and webcast on May 15, 2009, at 8:00 am (Eastern Time) to discuss the Company's selected preliminary financial results, business outlook, and related corporate and financial matters.

The live dial-in number is (877) 239-3024, conference ID code 98997560. Interested parties may also listen to a live webcast of the call by logging on to the Investor Relations section of AspenTech’s website, http://www.aspentech.com/corporate/investor.cfm, and clicking on the "webcast" link. A replay of the call will be archived on AspenTech’s website and will also be available via telephone at (800) 642-1687 or (706) 645-9291, conference ID code 98997560 through May 22, 2009.

About AspenTech

AspenTech is a leading supplier of software that optimizes process manufacturing – including oil and gas, petroleum, chemicals, pharmaceuticals and other industries that manufacture and produce products from a chemical process. With integrated aspenONE solutions, process manufacturers can implement best practices for optimizing their engineering, manufacturing and supply chain operations. As a result, AspenTech customers are better able to increase capacity, improve margins, reduce costs and become more energy efficient. To see how the world’s leading process manufacturers rely on AspenTech to achieve their operational excellence goals, visit www.aspentech.com.

Forward Looking Statements

This press release may contain forward-looking statements for purposes of the safe harbor provisions of the Private Securities Litigation Reform Act of 1995. Actual results may vary significantly from AspenTech’s expectations based on a number of risks and uncertainties, including, without limitation: AspenTech’s plan to improve operational performance may not be implemented effectively; AspenTech has identified material weaknesses in its internal controls with respect to software license revenue recognition and other matters, that, if not remedied effectively, could result in material misstatements; AspenTech may incur substantial damages and expenses as the result of pending and future securities litigation and government investigations, including securities litigation based on the restatements of the company’s financial statements as well as any future action associated with a determination that the company has failed to comply with its existing consent decree with the Federal Trade Commission; AspenTech’s lengthy sales cycle makes it difficult to predict quarterly operating results; fluctuations in AspenTech’s quarterly operating results; AspenTech’s dependence on customers in the cyclical chemicals, petrochemicals and petroleum industries; the possibility of new accounting standards or the interpretation of existing accounting standards affecting our financial results; AspenTech’s ability to raise additional capital as required; intense competition; AspenTech’s need to develop and market products successfully; reliance on relationships with strategic partners; challenges associated with international operations; risks associated with AspenTech’s delisting from The Nasdaq Stock Exchange and the trading of AspenTech’s common stock over the counter; and other risk factors described from time to time in AspenTech’s periodic reports filed with the Securities and Exchange Commission.

AspenTech cannot guarantee any future results, levels of activity, performance, or achievements. AspenTech expressly disclaims any current intention to update forward-looking statements after the date of this press release.