CDT Clean Diesel

Clean Diesel Technologies, Inc. (Nasdaq:CDTI) announced today that the employment of Ann B. Ruple as Vice President, Treasurer and Chief Financial Officer was terminated effective April 19, 2010.

On the same date, the Board of Directors of Clean Diesel appointed John Wynne, 48, as Vice President, Treasurer and Interim Chief Financial Officer effective April 23, 2010. Mr. Wynne has been a partner of Tatum, LLC since 2005. Tatum is an executive services firm and is providing Clean Diesel with Mr. Wynne's services as Interim Chief Financial Officer. During his association with Tatum, Mr. Wynne, who is a certified public accountant, served as Chief Financial Officer of Arbinet Corporation, a telecommunications company, from 2006 to 2009 and as Interim Chief Financial Officer of North American Airlines, Inc. from 2005 to 2006. Prior to his association with Tatum, Mr. Wynne held Chief Financial Officer positions with the Promptcare Companies, Inc., a health services company; Allied International Healthcare, Inc.; and Wassall USA, Inc., a conglomerate.

About Clean Diesel Technologies

Clean Diesel Technologies (Nasdaq:CDTI) is a cleantech company providing sustainable solutions to reduce emissions, increase energy efficiency and lower the carbon intensity of on- and off-road engine applications. Clean Diesel's patented technologies and products allow manufacturers and operators to comply with increasingly strict regulatory emissions and air quality standards, while also improving fuel economy and power.

The company's solutions significantly reduce emissions formed by the combustion of fossil fuels and biofuels, including particulate matter (PM), nitrogen oxides (NOx), carbon monoxide (CO) and hydrocarbons (HC)—without increasing secondary emissions such as nitrogen dioxide, NO2. As a result, they are effective for: OEMs, Tier 1 suppliers and retrofit providers; businesses entering the emissions control market seeking solutions and expertise; operators requiring compliant emissions solutions; fuel, biofuels and additive suppliers seeking low emissions and energy efficient products; and regulators creating public policy. Clean Diesel's solutions, therefore, are ideal for such markets as: on-road vehicles, construction, mining, agriculture, port/freight handling, locomotive, marine, and power generation.

Clean Diesel develops and manages intellectual property from original concept to full-scale commercial deployment. Building on its almost 300 granted and pending patents, its offerings include ARIS® selective catalytic reduction (SCR); the patented combination of SCR and exhaust gas recirculation (EGR); hydrocarbon injection for emissions control applications; Platinum Plus® Fuel-Borne Catalyst (FBC); the Purifier™ family of particulate filter systems; and its wire mesh filter particulate filter technologies. The company was founded in 1995 and is headquartered in Bridgeport, Connecticut. A wholly-owned subsidiary, Clean Diesel International, LLC is based in London, England. For more information, please visit www.cdti.com.

The Clean Diesel Technologies, Inc. logo is available at http://www.globenewswire.com/newsroom/prs/?pkgid=5742

CONTACT:  Clean Diesel Technologies, Inc.

          Charles W. Grinnell, General Counsel & Secretary

          203-416-5290

          cgrinnell@cdti.com