===============================================================================

                                                           +------------------+
                                 UNITED STATES             |   OMB APPROVAL   |
                      SECURITIES AND EXCHANGE COMMISSION   +------------------+
                            Washington, D.C. 20549         |   OMB Number:    |
                                                           |    3235-0058     |
                                  FORM 12b-25              |     Expires:     |
                                                           | January 31, 2002 |
                          NOTIFICATION OF LATE FILING      |     Estimated    |
                                                           |  average burden  |
(Check One): [X] Form 10-K  [ ] Form 20-F   [ ] Form 11-K  |   hours per      |
             [ ] Form 10-Q  [ ] Form N-SAR                 |  response..2.50  |
                         December 31, 2000                 +------------------+
For Period Ended: ________________________                 +------------------+
                                                           | SEC FILE NUMBER  |
                [ ] Transition Report on Form 10-K         |                  |
                [ ] Transition Report on Form 20-F         |      0-32261     |
                [ ] Transition Report on Form 11-K         +------------------+
                [ ] Transition Report on Form 10-Q         +------------------+
                [ ] Transition Report on Form N-SAR        |   CUSIP NUMBER   |
                                                           |    00208J 10 8   |
For the Transition Period Ended: ________________________  +------------------+

+------------------------------------------------------------------------------+
| Read Instruction (on back page) Before Preparing Form. Please Print or Type. |
|  Nothing in this form shall be construed to imply that the Commission has    |
|                 verified any information contained herein.                   |
+------------------------------------------------------------------------------+

If the notification relates to a portion of the filing checked above, identify
the Item(s) to which the notification relates:

- --------------------------------------------------------------------------------
PART I - REGISTRANT INFORMATION
        ATP Oil & Gas Corporation
- --------------------------------------------------------------------------------
Full Name of Registrant

- --------------------------------------------------------------------------------
Former Name if Applicable

        4600 Post Oak Place, Suite 200
- --------------------------------------------------------------------------------
Address of Principal Executive Office (Street and Number)

Houston, Texas 77027
- --------------------------------------------------------------------------------
City, State and Zip Code

PART II - RULES 12b-25(b) AND (c)

If the subject report could not be filed without unreasonable effort or expense
and the registrant seeks relief pursuant to Rule 12b-25(b), the following should
be completed. (Check box if appropriate)

    | (a)  The reasons described in reasonable detail in Part III of this form
    |      could not be eliminated without unreasonable effort or expense;
    | (b)  The subject annual report, semi-annual report, transition report on
    |      Form 10-K, Form 20-F, 11-K or Form N-SAR, or portion thereof, will be
    |      filed on or before the fifteenth calendar day following the
[X] |      prescribed due date; or the subject quarterly report of transition
    |      report on Form 10-Q, or portion thereof will be filed on or before
    |      the fifth calendar day following the prescribed due date; and
    | (c)  The accountant's statement or other exhibit required by Rule
    |      12b-25(c) has been attached if applicable.

PART III - NARRATIVE

State below in reasonable detail the reasons why Forms 10-K, 20-F, 11-K, 10-Q,
N-SAR, or the transition report or portion thereof, could not be filed within
the prescribed time period.
                                               (Attach Extra Sheets if Needed)

Shortly before completion of the audit of the Company's financial statements for
the year ended December 31, 2000, the Company became aware of the required
treatment in its accounting for two gas contracts which resulted in an
unexpected delay in the completion of its audit. As a result, the Company was
unable to file its Form 10-K on April 2, 2001, the filing due date. The audit is
expected to be completed shortly and the Form 10-K is expected to be filed on or
prior to April 6, 2001.


PART IV - OTHER INFORMATION

(1)  Name and telephone number of person to contact in regard to this
     notification.

        Albert L. Reese, Jr.            (713)               403-5514
     ----------------------------    --------------    -------------------------
               (Name)                 (Area Code)         (Telephone Number)

(2)  Have all other periodic reports required under Section 13 or 15(d) of
     the Securities Exchange Act of 1934 or Section 30 of the Investment Company
     Act of 1940 during the preceding 12 months or for such shorter period that
     the registrant was required to file such report(s) been filed? If answer is
     no, identify report(s).                                [X] Yes [ ] No
     ---------------------------------------------------------------------------
(3)  Is it anticipated that any significant change in results of operations
     from the corresponding period for the last fiscal year will be reflected by
     the earnings statements to be included in the subject report or portion
     thereof?                                               [X] Yes  [ ] No

     If so, attach an explanation of the anticipated change, both narratively
     and quantitatively, and, if appropriate, state the reasons why a reasonable
     estimate of the results cannot be made.

The Company's results of operations for the year ended December 31, 2000 reflect
significant changes from its results of operation for the year ended
December 31, 1999 due to the growth of the Company's business. These changes are
set forth in the Company's Form 10-K for the year ended December 31, 2000, which
is expected to be filed with the Commission on or prior to April 6, 2001.


================================================================================

                           ATP Oil & Gas Corporation
          -----------------------------------------------------------
                 (Name of Registrant as Specified in Charter)

has caused this notification to be signed on its behalf by the undersigned
hereunto duly authorized.

Date April 3, 2001                      By /s/ Albert L. Reese, Jr.
    ------------------------------        --------------------------------------
                                          Senior Vice President and
                                          Chief Financial Officer


INSTRUCTION:  The form may be signed by an executive officer of the registrant
or by any other duly authorized representative.  The name and title of the
person signing the form shall be typed or printed beneath the signature.  If the
statement is signed on behalf of the registrant by an authorized representative
(other than an executive officer), evidence of the representative's authority to
sign on behalf of the registrant shall be filed with the form.

+----------------------------------ATTENTION-----------------------------------+
|                INTENTIONAL MISSTATEMENTS OR OMISSIONS OF FACT                |
|         CONSTITUTE FEDERAL CRIMINAL VIOLATIONS (SEE 18 U.S.C. 1001).         |
+------------------------------------------------------------------------------+
                             GENERAL INSTRUCTIONS

1.  This form is required by Rule 12b-25 (17 CFR 240.12b-25) of the General
    Rules and Regulations under the Securities Exchange Act of 1934.

2.  One signed original and four conformed copies of this form and amendments
    thereto must be completed and filed with the Securities and Exchange
    Commission, Washington, D.C. 20549, in accordance with Rule 0-3 of the
    General Rules and Regulations under the Act. The information contained in or
    filed with the form will be made a matter of public record in the Commission
    files.

3.  A manually signed copy of the form and amendments thereto shall be filed
    with each national securities exchange on which any class of securities of
    the registrant is registered.

4.  Amendments to the notifications must also be filed on form 12b-25 but need
    not restate information that has been correctly furnished.  The form shall
    be clearly identified as an amended notification.

5.  Electronic Filers.  This form shall not be used by electronic filers unable
    to timely file a report solely due to electronic difficulties.  Filers
    unable to submit a report within the time period prescribed due to
    difficulties in electronic filing should comply with either Rule 201 or
    Rule 202 of Regulation S-T ((S)232.201 or (S)232.202 of this chapter) or
    apply for an adjustment in filing date pursuant to Rule 13(b) of Regulation
    S-T ((S)232.13(b) of this chapter).


SEC 1344 (2-99)


Exhibit

ATP Oil & Gas Corporation

Houston, Texas

April 3, 2001

Ladies and Gentlemen:

Pursuant to Rule 12b-25 of the General Rules and Regulations under the
Securities and Exchange Act of 1934, we inform you that we have been furnished a
copy of Form 12b-25 to be filed by ATP Oil & Gas Corporation on April 3, 2001,
which contains notification of the registrant's inability to file its Form 10-K
by April 2, 2001.  We have read the Company's statements contained in Part III
therein and we agree with the stated reason as to why we were unable to complete
our audit and report on the consolidated financial statements for the year ended
December 31, 2000 by April 2, 2001, to be included in the Form 10-K.

Very truly yours,

/s/ KPMG LLP