Registration No. 333-182009

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, DC 20549

Post-Effective Amendment No. 1
to
FORM S-8

REGISTRATION STATEMENT

Under

the Securities Act of 1933

CLEAN DIESEL TECHNOLOGIES, INC.

(Exact name of registrant as specified in its charter)

New Employee Inducement Award Nonqualified Stock Option

 (Full title of the plan)

David E. Shea

Chief Financial Officer and Treasurer

1621 Fiske Place

Oxnard, California 93033

(805) 639-9458

(Name, address, and telephone number of agent for service)

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, or a smaller reporting company. See the definitions of “large accelerated filer,” “accelerated filer” and “smaller reporting company” in Rule 12b-2 of the Exchange Act.

DEREGISTRATION OF SECURITIES

Pursuant to the requirements of the Securities Act of 1933, the Registrant certifies that it has reasonable grounds to believe that it meets all of the requirements for filing on Form S-8 and has duly caused this Registration Statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of Oxnard, State of California, on this 7th day of August, 2015.