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): May 11, 2006

Gulf Island Fabrication, Inc.

(Exact name of registrant as specified in its charter)

(985) 872-2100

(Registrant’s telephone number, including area code)

N/A

(Former name or former address, if changed since last report)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligations 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 1.01 Entry Into a Material Definitive Agreement

On May 11, 2006, the Company, as borrower, Whitney National Bank and JPMorgan Chase Bank, N.A., as lenders, and the guarantors specified therein, entered into the Fifth Amendment to Ninth Amended and Restated Credit Agreement (as amended, the “Credit Facility”). The amendment, which is effective March 31, 2006, extends the term of the Credit Facility from July 31, 2008 to December 31, 2008, and also facilitates certain banking services and certain guarantees.

SIGNATURE

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.

Dated: May 16, 2006

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