As filed with the Securities and Exchange Commission on September 21, 2005
                                   Registration Nos. 333-117953
   --------------------------------------------------------------------------


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

                        POST-EFFECTIVE AMENDMENT NO. 1 TO
                                    FORM S-8
                          REGISTRATION STATEMENT UNDER
                           THE SECURITIES ACT OF 1933
                           --------------------------


                             ESCO TECHNOLOGIES INC.
             (Exact Name of Registrant as Specified in Its Charter)

       Missouri                                             43-1554045
(State or Other Jurisdiction of Incorporation            (I.R.S. Employer )
 or Organization)                                         Identification No.

                               9900A Clayton Road
                            St. Louis, MO 63124-1186
          (Address of Principal Executive Offices, Including Zip Code)
          ------------------------------------------------------------

                ESCO TECHNOLOGIES INC. 2001 STOCK INCENTIVE PLAN
             ESCO TECHNOLOGIES INC. 2004 INCENTIVE COMPENSATION PLAN
                            (Full title of the Plan)

                             Alyson S. Barclay, Esq.
                  Vice President, Secretary and General Counsel
                             ESCO Technologies Inc.
                               9900A Clayton Road
                            St. Louis, MO 63124-1186
                                 (314) 213-7200
 (Name, Address and Telephone Number, Including Area Code, of Agent For Service)
 -------------------------------------------------------------------------------



                                EXPLANATORY NOTE

This  Post-Effective  Amendment to the ESCO  Technologies  Inc. (the  "Company")
Registration  Statements  on Form  S-8  (Nos.  333-117953  and  333-85268)  (the
"Registration Statements"),  which relate to the Company's equity-based employee
benefit  plans,  is filed by the  Company  pursuant  to  Rule 416(b)  under  the
Securities  Act of 1933,  as amended (the  "Securities  Act"),  to reflect a one
hundred  percent  increase  in the number of shares of common  stock,  $0.01 par
value,  of the  Company  (the  "Common  Stock")  covered  by  such  Registration
Statements as a result of the Company's  two-for-one stock split effected in the
form of a one hundred  percent stock  dividend  payable  September 23,  2005, to
shareholders of record on September 9, 2005.

Pursuant to Rule 416(a) under the Securities  Act, the  Registration  Statements
are also  amended to cover any  additional  shares of Common  Stock which may be
issued under the applicable equity-based  compensation plans to prevent dilution
resulting  from  any  subsequent  stock  splits,   stock  dividends  or  similar
transactions.

The contents of the Registration Statements are hereby incorporated by reference
pursuant to General Instruction E on Form S-8.

PART I   INFORMATION REQUIRED IN THE SECTION 10(a) PROSPECTUS

Item 1.  Plan Information.

          Not required to be filed with this Registration Statement.

Item 2. Registrant Information and Employee Plan Annual Information.

          Not required to be filed with this Registration Statement.

PART II  INFORMATION REQUIRED IN THE REGISTRATION STATEMENT

Item 3. Incorporation of Documents by Reference.

          Not required to be filed with this Registration  Statement pursuant to
          General Instruction E on Form S-8.

Item 4. Description of Securities.

          Not required to be filed with this Registration  Statement pursuant to
          General Instruction E on Form S-8.

Item 5. Interests of Named Experts and Counsel.

          Not required to be filed with this Registration  Statement pursuant to
          General Instruction E on Form S-8.


Item 6. Indemnification of Directors and Officers.

          Not required to be filed with this Registration  Statement pursuant to
          General Instruction E on Form S-8.

Item 7. Exemption from Registration Claimed.

          Not applicable.

Item 8. Exhibits.

Exhibit No.      Description        Filed Herewith or Incorporated by Reference

4.1 Specimen Common Stock Certificate Incorporated  by reference  to  Form 10-Q
                                      for the fiscal  quarter  ended  June 30,
                                      2000, at Exhibit 4(a)

4.2 Specimen Rights Certificate        Incorporated  by reference  to Current
                                       Report on Form 8-K dated February 3,
                                       2000,  at Exhibit B to Exhibit 4.1

4.3 Rights Agreement dated as of       Incorporated  by reference  to Current
    September 24, 1990 (as amended     Report on  Form  8-K  dated February 3,
    and  restated  as  of February 3,  2000, at Exhibit 4.1
    2000)  between the  Registrant
    and  Registrar and Transfer
    Company, as successor Rights Agent

4.4 Credit  Agreement  dated  as  of   Incorporated  by reference to Form 10-K
    October 6, 2004, among the         for the fiscal year ended September 30,
    Registrant,  Wells Fargo Bank,     2004, at Exhibit 4.4
    N.A., as  agent, and the
    lenders listed therein

5   Opinion of Counsel

23.1 Consent of Counsel (included
     in Exhibit 5)

23.2 Consent of KPMG LLP

24   Power of Attorney (included
     on the Signatures pages
     of the Registration Statements)


Item 9.Undertakings

          Not required to be filed with this Registration  Statement pursuant to
          General Instruction E on Form S-8.

                                   SIGNATURES

Pursuant to the  requirements  of the  Securities  Act of 1933,  the  Registrant
certifies  that it has  reasonable  grounds to believe  that it meets all of the
requirements  for  filing  on Form S-8 and has  duly  caused  this  Registration
Statement  to be  signed  on its  behalf  by  the  undersigned,  thereunto  duly
authorized,  in the  city of  Ladue,  state  of  Missouri,  on this  20th day of
September, 2005.

                                              ESCO TECHNOLOGIES INC.

                                              By: /s/ T.B. Martin
                                                  ----------------
                                                  T.B. Martin
                                                  Assistant Secretary and
                                                  Associate General Counsel

Pursuant to the  requirements of the Securities Act of 1933,  this  registration
statement has been signed by the following  persons in the capacities and on the
date indicated.

Signature                                      Title                 Date

/s/ *                Chairman, Chief Executive Officer and    September 20, 2005
- ----------------     Director (principal executive officer)
V. L. Richey, Jr.

/s/ *                President, Chief Operating Officer and  September 20, 2005
- ----------------     Director
C. J. Kretschmer

/s/ *                Vice President and Chief Financial      September 20, 2005
- --------------       Officer (principal financial and
G. E. Muenster       accounting officer)

/s/ *                 Director                               September 20, 2005
- ---------------
W. S. Antle III

/s/ *                 Director                               September 20, 2005
- ---------------
J. M. McConnell

/s/ *                 Director                               September 20, 2005
- ------------
L. W. Solley

/s/ *                  Director                              September 20, 2005
- -------------
J. M. Stolze

/s/ *                  Director                               September 20, 200
- --------------
D. C. Trauscht

/s/ *                  Director                              September 20, 2005
- ------------
J. D. Woods

*/s/T.B. Martin                                              September 20, 2005
- ---------------
T.B. Martin
Assistant Secretary and
Associate General Counsel
By power of attorney



                                  EXHIBIT INDEX

Exhibits are listed by number  corresponding to the Exhibit Table of Item 601 in
Regulation S-K.

5             Opinion of Counsel.
23.1          Consent of Counsel (included in Exhibit 5)
23.2          Consent of KPMG LLP.
24            Power of Attorney (included on the Signatures pages of the
              Registration Statements)

See Item 8 for a list of exhibits incorporated by reference.

                                                                       EXHIBIT 5


                                       September 20, 2005




ESCO Technologies Inc.
9900A Clayton Road
St. Louis, MO  63124-1186

Ladies and Gentlemen:

     I am Assistant Secretary and Associate General Counsel of ESCO Technologies
Inc., a Missouri corporation (the "Company"), and in such capacity I am familiar
with the  Post-Effective  Amendment No. 1 to the Registration  Statement on Form
S-8 (the  "Post-Effective  Amendment")  relating  to the  Company's  2001  Stock
Incentive Plan and 2004 Incentive  Compensation Plan (the "Plans") to which this
letter is filed as an exhibit. The Post-Effective  Amendment registers 2,105,365
shares of the  Company's  common  stock,  par value $0.01 per share (the "Common
Stock"),   offered  pursuant  to  stock  options,   stock  appreciation  rights,
performance share awards,  restricted stock awards and other stock-based awards,
granted and which may be granted under the Plans,  including the Preferred Stock
Purchase  Rights  associated  with such Common  Stock (the Common  Stock and its
associated Preferred Stock Purchase Rights, the "Securities").

     I have examined originals or copies,  certified or otherwise  identified to
my satisfaction,  of such documents,  corporate records,  certificates of public
officials  and other  instruments  as I deemed  necessary for the purpose of the
opinion expressed herein.

     On the basis of the  foregoing,  I am of the opinion  that the  Securities,
when sold or distributed in accordance with the provisions of the Plans, will be
legally issued, fully paid and non-assessable.

     I consent to the filing of this letter as an exhibit to the  Post-Effective
Amendment.

                                                    Very truly yours,


                                                    /s/ Thomas B. Martin_____
                                                    Thomas B. Martin

TBM/bjo

Enclosures


                                                                 EXHIBIT 23.2








            Consent of Independent Registered Public Accounting Firm



The Board of Directors
ESCO Technologies Inc.:

We consent to the use of our reports dated  November 9, 2004 with respect to the
consolidated  balance sheets of ESCO  Technologies Inc. as of September 30, 2004
and 2003, and the related consolidated  statements of operations,  shareholders'
equity,  and cash  flows for each of the years in the  three-year  period  ended
September  30, 2004,  and related  financial  statement  schedule,  incorporated
herein by  reference  in this  post-effective  amendment  No. 1 to  registration
statement on Form S-8 of ESCO Technologies Inc.

Our reports refer to a change in accounting  for the  consolidation  of variable
interest entities on July 1, 2003.


/s/ KPMG LLP
    KPMG LLP

St. Louis, Missouri
September 21, 2005