MENLO PARK, CA, February 6, 2006 /PRNewswire — Ultra Clean Holdings, Inc. (Nasdaq: UCTT), the parent company of Ultra Clean Technology Systems and Service, Inc., announced today that it intends to file a registration statement with respect to the offering by it of 2,000,000 shares of its common stock and by certain of its stockholders of 4,000,000 shares of its common stock in an underwritten public offering. The selling stockholders also intend to grant the underwriters a 30 day option to purchase up to an additional 900,000 shares of the company’s common stock, solely to cover over allotments.

Ultra Clean intends to use the net proceeds to be received by it from the offering for working capital and other general corporate purposes, including potential acquisitions of companies or technologies that complement its business.

This press release does not constitute an offer to sell or the solicitation of an offer to buy, nor will there be any sale of these securities in any state in which such offer, solicitation or sale would be unlawful prior to registration or qualification under the securities laws of any such state, and is issued pursuant to Rule 135 under the Securities Act of 1933, as amended.

About Ultra Clean Holdings, Inc.
Ultra Clean Holdings, Inc. is a developer and supplier of critical subsystems for the semiconductor capital equipment industry.  Ultra Clean offers its customers a complete outsourced solution for gas delivery systems and other subassemblies, improved design-to-delivery cycle times, component neutral design and manufacturing and component testing capabilities. Ultra Clean's customers are primarily original equipment manufacturers of semiconductor capital equipment. Ultra Clean is headquartered in Menlo Park, California. Additional information is available at www.uct.com.

Safe Harbor Statement
The foregoing information contains, or may be deemed to contain, "forward- looking statements" (as defined in the U.S. Private Securities Litigation Reform Act of 1995) which reflect our current views with respect to future events and financial performance. We use words such as "anticipates," "believes," "plan," "expect," "future,"' "intends," "may," "will," "should," "estimates," "predicts," "potential," "continue" and similar expressions to identify these forward-looking statements.  Forward looking statements included in the press release include estimates made with respect to our fourth quarter revenue and diluted earnings per share and purchase orders placed by a significant customer for the manufacture of entire process modules.  All forward-looking statements address matters that involve risks and uncertainties. Accordingly, our actual results may differ materially from the results predicted or implied by these forward- looking statements. These risks, uncertainties and other factors include, among others, those identified in "Risk Factors," "Management's Discussion and Analysis of Financial Condition and Results of Operations'' and elsewhere in our annual report on Form 10-K for the year ended December 31, 2004 filed with the Securities and Exchange Commission. Ultra Clean Holdings, Inc. undertakes no obligation to publicly update or review any forward-looking statements, whether as a result of new information, future developments or otherwise.