MHI Pioneer Municipal High Income Fund Inc

Pioneer Investments announced today that it will hold a conference call regarding Pioneer Municipal High Income Trust (NYSE: MHI) and Pioneer Municipal High Income Advantage Trust (NYSE: MAV) with Portfolio Managers David Eurkus and Timothy Pynchon. The purpose of the call is to discuss the 2009 performance of each fund and their current positioning. The conference call will be open to the public.

The call will be held on Thursday, February 4, 2010 at 4:00 PM ET and can be accessed by calling (866) 360-7030. Conference ID # 53241917. The call will be available on replay for seven days following the call at (800) 642-1687. Conference ID # 53241917. A transcript will be posted to pioneerinvestments.com.

Pioneer Investment Management, Inc., the investment advisor for this fund, is part of Pioneer Investment Management USA Inc., the U.S. subsidiary of Pioneer Global Asset Management S.p.A.

Shareholder Inquiries:   Please contact your financial advisor or visit pioneerinvestments.com   Broker/Advisor Inquiries Please Contact: 800-622-9876   Media Inquiries Please Contact: Geoff Smith (617) 422-4727  

Closed-end funds, unlike open-end funds, are not continuously offered. There is a one-time public offering and once issued, common shares of closed-end funds are sold in the open market through a stock exchange and frequently trade at prices lower than their net asset value. Net asset value (NAV) is total assets less total liabilities divided by the number of common shares outstanding.

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