UNITED STATES
SECURITIES AND EXCHANGE COMMISSION

FORM 8-K/A

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

Date of Report (Date of Earliest Event Reported): April 28, 2005

UNITED DEFENSE INDUSTRIES, INC.

1525 Wilson Boulevard, Suite 700
Arlington, Virginia 22209
(Address of principal executive offices) (ZIP Code)

Registrant’s telephone number, including area code:
(703) 312-6100

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 (see General Instruction A.2. below):

o Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)
o Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)
o Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))
o Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Item 2.02. Results of Operations and Financial Condition.

The following information is furnished under Item 2.02, “Results of Operations and Financial Condition.” This information shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), or incorporated by reference in any filing under the Securities Act of 1933, as amended, or the Exchange Act, except as shall be expressly set forth by specific reference in such filing.

On April 28, 2005, United Defense Industries, Inc. issued a press release announcing certain financial and operating results for the first quarter of 2005 and filed a Current Report on Form 8-K. A copy of the press release was filed as exhibit 99.1 to the Form 8-K. This Amendment is being filed because the conformed signature to the Form 8-K was inadvertently omitted.

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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.

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