Clean Diesel Technologies to File 2009 Form 10-K on March 31, 2010

Clean Diesel Technologies, Inc. (Nasdaq:CDTI), the cleantech emissions reduction company providing sustainable solutions to reduce emissions, increase energy efficiency and lower the carbon intensity of on- and off-road engine applications, announces it will file its Annual Report on Form 10-K for 2009 with the U.S. Securities and Exchange Commission (SEC) after the close of trading on March 31, 2010. Earnings for the fourth quarter of 2009 and full-year 2009 will be released the following morning, April 1, 2010.

Previously, CDTI has been required to file its Form 10-K as an accelerated filer, meaning it would have had to file on March 15. However, the company is no longer classified as an accelerated filer and, therefore, is not subject to that requirement.

About Clean Diesel Technologies, Inc.

Clean Diesel Technologies 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—without increasing secondary emissions, such as nitrogen dioxide (NO2)—including particulate matter (PM), nitrogen oxides (NOx), carbon monoxide (CO) and hydrocarbons (HC). As a result, they are effective for: OEMs, Tier 1 suppliers and retrofit providers; businesses seeking solutions and expertise upon entering the emissions control market; operators requiring compliant emissions solutions; fuel, biofuel and additive suppliers seeking low emissions and energy efficient products; and regulators creating public policy. Clean Diesel's solutions, therefore, are ideal for on-road vehicles and applications in a wide range of industries, including 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 almost 200 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 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 on London.

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

Ann B. Ruple, CPA, Chief Financial Officer,

Vice President & Treasurer

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