UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549

                                   FORM 10-K/A
                                (Amendment No. 3)

    |X|       ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE
                         SECURITIES EXCHANGE ACT OF 1934
                   For the fiscal year ended December 31, 2005
                                       OR
    |_|     TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE
                         SECURITIES EXCHANGE ACT OF 1934

           For the transition period from ____________ to ____________

                        Commission file number: 000-21644

                            CRIMSON EXPLORATION INC.
             (Exact name of registrant as specified in its charter)

               Delaware                                      20-3037840
    (State or other jurisdiction of                       (I.R.S. Employer
     incorporation or organization)                      Identification No.)

480 N. Sam Houston Parkway East, Suite 300
              Houston, Texas                                   77060
 (Address of principal executive offices)                    (Zip Code)

                                 (281) 820-1919
              (Registrant's telephone number, including area code)

           Securities registered pursuant to Section 12(b) of the Act:

    Securities registered pursuant to Section 12(g) of the Act: Common Stock,
                           $0.001 par value per share

Indicate by check mark if the registrant is a well-known seasoned issuer, as
defined in Rule 405 of the Securities Act.
Yes [ ] No [X]

Indicate by check mark if the registrant is not required to file reports
pursuant to Section 13 or Section 15(d) of the Exchange Act. Yes [ ] No [X]

Indicate by check mark whether the registrant (1) has filed all reports required
to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during
the preceding 12 months (or for such shorter period that the registrant was
required to file such reports), and (2) has been subject to such filing
requirements for the past 90 days. Yes [X] No [ ]

Indicate by check mark if disclosure of delinquent filers pursuant to Item 405
of Regulation S-K is not contained herein, and will not be contained, to the
best of registrant's knowledge, in definitive proxy or information statements
incorporated by reference in Part III of this Form 10-K or any amendment to this
Form 10-K. [ ]

Indicate by check mark whether the registrant is a large accelerated filer, an
accelerated filer, or a non-accelerated filer. See definition of "accelerated
filer" and "large accelerated filer" in Rule 12b-2 of the Exchange Act.

Large accelerated filer [ ]   Accelerated filer [ ]   Non-accelerated filer [X]

Indicate by check mark whether the registrant is a shell company (as defined in
Rule 12b-2 of the Exchange Act). Yes [ ] No [X]

As of June 30, 2005, the aggregate market value of the registrant's common stock
held by non-affiliates of the registrant was $18,010,865 based on the closing
sales price of $0.98 of the common stock. For purposes of this computation, all
executive officers, directors and 10% beneficial owners of the registrant are
deemed to be affiliates. Such a determination should not be deemed an admission
that such executive officers, directors and 10% beneficial owners are
affiliates.

On March 29, 2006, there were 33,041,332 shares of common stock outstanding.


                       DOCUMENTS INCORPORATED BY REFERENCE

Portions of our Definitive Proxy Statement for the 2006 Annual Meeting, expected
to be filed within 120 days of our fiscal year end, are incorporated by
reference into Part III.




                                EXPLANATORY NOTE

We are filing this Amendment No. 3 on Form 10-K/A to the Crimson Exploration
Inc. Annual Report on Form 10-K for the year ended December 31, 2005 to amend
and restate Part II, Item 9A, in response to comments received by the Company
from the Commission's Staff pursuant to its review of the Company's
post-effective amendment no. 3 to its Registration Statement on Form S-1 (Reg.
No. 333-116048).

The following item is included in this amendment:

Part II - Item 9A.  Controls and Procedures

In addition, this amendment includes the following exhibits:

Exhibit 31.1 - Certification of Chief Executive Officer pursuant to Section 302
of the Sarbanes-Oxley Act of 2002.

Exhibit 31.2 - Certification of Chief Financial Officer pursuant to Section 302
of the Sarbanes-Oxley Act of 2002.

Exhibit 32 - Certification of Chief Executive Officer and Chief Financial
Officer pursuant to Section 906 of the Sarbanes-Oxley Act of 2002.

This Amendment No.3 on Form 10-K/A does not reflect events occurring after the
filing of our Annual Report on Form 10-K on March 31, 2006, the filing of
Amendment No.1 on Form 10-K/A on April 27, 2006 and the filing of Amendment No.2
on Form 10-K/A on June 9, 2006 or include, or otherwise modify or update, the
disclosure contained therein in any way except as expressly indicated above.




                                     PART II

ITEM 9A. Controls and Procedures.

Our president and chief executive officer and our chief financial officer have
concluded, based on their evaluation as of the end of the period covered by this
Form 10-K, that our disclosure controls and procedures, as defined under Rules
13a-15(e) and 15d-15(e) of the Securities Exchange Act of 1934, as amended, are
effective to ensure that information we are required to disclose in the reports
we file or submit under the Exchange Act is recorded, processed, summarized and
reported within the time periods specified in the SEC's rules and forms, and
that our disclosure controls and procedures are effective to ensure that
information we are required to disclose in such reports is accumulated and
communicated to management, including our president and chief executive officer
and our chief financial officer, as appropriate to allow timely decisions
regarding required disclosure.

During the period covered by this report, there has been no change in our
internal controls over financial reporting that materially affected, or is
reasonably likely to material affect, these controls.




                                     PART IV

ITEM 15. Exhibits.

Number         Description
------         -----------

31.1*          Certification of Chief Executive Officer pursuant to Section 302
               of the Sarbanes-Oxley Act of 2002.

31.2*          Certification of Chief Financial Officer pursuant to Section 302
               of the Sarbanes-Oxley Act of 2002.

32*            Certification of Chief Executive Officer and Chief Financial
               Officer pursuant to Section 906 of the Sarbanes-Oxley Act of
               2002.

* Filed herewith.




                                   SIGNATURES

     Pursuant to the requirements of Section 13 or 15(d) of the Securities
Exchange Act of 1934, the registrant has duly caused this report to be signed on
its behalf by the undersigned, thereunto duly authorized.

                                                    CRIMSON EXPLORATION INC.

Date: July 17, 2006                                 By /s/ Allan D. Keel
                                                       -------------------------
                                                       Allan D. Keel, President

     Pursuant to the requirements of the Securities Exchange Act of 1934, this
report has been signed below by the following persons, on behalf of the
registrant, and in the capacities and on the dates indicated.

             Signature                         Title                    Date
             ---------                         -----                    ----

/s/ Allan D. Keel                  President, Chief Executive      July 17, 2006
--------------------------------   Officer and Director
Allan D. Keel

/s/ E. Joseph Grady                Senior Vice President and Chief July 17, 2006
--------------------------------   Financial Officer
E. Joseph Grady

/s/ Richard L. Creel               Vice President Finance and      July 17, 2006
--------------------------------   Chief Accounting Officer
Richard L. Creel

*                                  Director                        July 17, 2006
--------------------------------
Skardon F. Baker

*                                  Director                        July 17, 2006
--------------------------------
B. James Ford

*                                  Director                        July 17, 2006
--------------------------------
Lon McCain

*                                  Director                        July 17, 2006
--------------------------------
Lee S. Backsen

/s/ Allan D. Keel
--------------------------------
Allan D. Keel, Attorney-in-Fact
pursuant to a power of attorney
previously granted