(Check One):                               UNITED STATES                               SEC FILE
     |_|   Form 10-K              SECURITIES AND EXCHANGE COMMISSION                    NUMBER
     |_|   Form 20-F                     Washington, D.C. 20549                        001-31258
     |_|   Form 11-K
     |X|   Form 10-Q                         FORM 12b-25                                CUSIP
     |_|   Form N-SAR                                                                   NUMBER
     |_|   Form N-CSR                  NOTIFICATION OF LATE FILING







                               For Period Ended: March 31, 2005
                               |_|   Transition Report on Form 10-K
                               |_|   Transition Report on Form 20-F
                               |_|   Transition Report on Form 11-K
                               |_|   Transition Report on Form 10-Q
                               |_|   Transition Report on Form N-SAR

                               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:




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                        PART I -- REGISTRANT INFORMATION



                        Anteon International Corporation
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                             Full Name of Registrant


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                            Former Name if Applicable

                         3211 Jermantown Road, Suite 700
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            Address of Principal Executive Office (Street and Number)

                                Fairfax, VA 22030
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                            City, State and Zip Code

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                       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 reason  described  in  reasonable  detail in Part III of this form
          could not be eliminated without unreasonable effort or expense

|X|  (b)  The subject annual report,  semi-annual  report,  transition report on
          Form 10-K,  Form 20-F, Form 11-K, Form N-SAR or Form N-CSR, or portion
          thereof,  will be  filed  on or  before  the  fifteenth  calendar  day
          following the prescribed due date; or the subject  quarterly report or
          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 why Forms 10-K, 20-F, 11-K, 10-Q, N-SAR, N-CSR,
or the  transition  report or  portion  thereof,  could not be filed  within the
prescribed     time     period.     (Attach     Extra    Sheets    if    Needed)
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Shortly before the filing deadline for the Registrant's Quarterly Report on Form
10-Q for the period ended March 31, 2005, the Registrant became aware of certain
generalized allegations made by an exiting employee relating to revenue accruals
during the third and fourth quarters of 2004 at one of the Registrant's business
units.  In  accordance  with its  internal  procedures,  Registrant  immediately
notified Registrant's Audit Committee of these allegations.  The Audit Committee
has engaged outside advisors to review matters related to these allegations.

Because these  allegations  were raised very shortly before the filing  deadline
for the  Registrant's  Quarterly  Report on Form 10-Q for the period ended March
31, 2005,  the work related to these matters  could not be  completed.  However,
based upon the inquiry to date, the  Registrant  has not identified  information
that would result in a material  change in the  previously  announced  financial
results for the quarter and year ended  December 31, 2004 and the quarter  ended
March 31, 2005.  Assuming there are no new  developments  on this matter and the
Audit Committee completes its review, the Registrant currently believes that the
Quarterly  Report on Form 10-Q for the period ended March 31, 2005 will be filed
within the extension  period provided by Rule  12b-25(b).

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                          PART IV-- OTHER INFORMATION

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

           Curtis L. Schehr,
         Senior Vice President,
      General Counsel & Secretary          703                  246-0200
- ----------------------------------       -------             ---------------
            (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). Yes |X| No |_|


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     (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? Yes |_| No |X|

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.




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                        Anteon International Corporation
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                  (Name of Registrant as Specified in Charter)

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



Date  May 11, 2005                            By: /s/ Curtis L. Schehr
                                              ----------------------------------

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 reports within the time period prescribed due to difficulties in
   electronic filing should comply with either Rule 201 or Rule 202 of
   Regulation S-T (ss.232.201 or ss.232.202 of this chapter) or apply for an
   adjustment in filing date pursuant to Rule 13(b) of Regulation S-T
   (ss.232.13(b) of this chapter).