CommonWealth REIT to Present at the REITWeek 2011: NAREIT Investor Forum on June 8, 2011

CommonWealth REIT (NYSE: CWH) today announced that John Popeo, Chief Financial Officer, will be presenting at the REITWeek 2011: NAREIT Investor Forum in New York City on Wednesday, June 8, 2011 at 8:00 a.m. Eastern Time.

A live audio webcast of the presentation will be available in a listen-only mode on the company’s website, which is located at www.cwhreit.com. Participants wanting to access the webcast should visit the company’s website about 15 minutes before the start of the presentation.

CommonWealth REIT is a real estate investment trust, or REIT, which primarily owns office and industrial properties located throughout the United States. As of March 31, 2011, CWH owned 490 properties with 66.0 million square feet, including 17.9 million square feet of leased industrial and commercial lands in Oahu, Hawaii and 11 properties with a combined 1.8 million square feet in Australia. CWH is headquartered in Newton, MA.

WARNING REGARDING FORWARD LOOKING STATEMENTS

THIS PRESS RELEASE CONTAINS FORWARD LOOKING STATEMENTS WITHIN THE MEANING OF THE PRIVATE SECURITIES LITIGATION REFORM ACT OF 1995 AND THE FEDERAL SECURITIES LAWS. THESE FORWARD LOOKING STATEMENTS ARE BASED UPON CWH’S PRESENT BELIEFS AND EXPECTATIONS, BUT THESE STATEMENTS AND THE IMPLICATIONS OF THESE STATEMENTS ARE NOT GUARANTEED TO OCCUR. FOR EXAMPLE, MR. POPEO’S PRESENTATION MAY BE RESCHEDULED TO A DIFFERENT DATE OR TIME OR CANCELLED DUE TO SCHEDULING CONFLICTS OR OTHER REASONS. INVESTORS ARE CAUTIONED NOT TO PLACE UNDUE RELIANCE UPON ANY FORWARD LOOKING STATEMENTS.

A Maryland Real Estate Investment Trust with transferable shares of beneficial interest listed on the New York Stock Exchange. No shareholder, Trustee or officer is personally liable for any act or obligation of the Trust.