UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934

Date of Report (Date of earliest event reported)

September 30, 2005

CERADYNE, INC.

(Exact name of registrant as specified in its charter)

Delaware	000-13059	33-0055414
(State or other jurisdiction of incorporation)	(Commission File Number)	(IRS Employer Identification No.)

3169 Red Hill Avenue, Costa Mesa, CA	92626
(Address of principal executive offices)	(Zip Code)

Registrant’s telephone number, including area code: (714) 549-0421

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

¨ Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

¨ Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

¨ Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

¨ Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Item 7.01 Regulation FD Disclosure.

On September 30, 2005 Ceradyne, Inc. issued a press release announcing the receipt of a $9.1 million order for its lightweight ceramic armor systems for the U.S. Army and Marine Corps. A copy of this press release is being furnished as Exhibit 99.1 to this Current Report on Form 8-K.

In accordance with General Instruction B.2 of Form 8-K, the information in this Current Report on Form 8-K, including Exhibit 99.1, shall not be deemed “filed” for the purposes of Section 18 of the Securities Exchange Act of 1934 or otherwise subject to the liability of that section, nor shall it be deemed incorporated by reference in any filing under the Securities Act of 1933.

Item 9.01 Financial Statements and Exhibits.

(c) Exhibits.

Exhibit Number	Description
99.1	Press release of Ceradyne, Inc. dated September 30, 2005.

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SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the Registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

	CERADYNE, INC.
September 30, 2005	By:	/s/ Jerrold J. Pellizzon
		Jerrold J. Pellizzon
		Chief Financial Officer and Secretary

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EXHIBIT INDEX

Exhibit Number	Description
99.1	Press release of Ceradyne dated September 30, 2005.

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