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                               UNITED STATES
                    SECURITIES AND EXCHANGE COMMISSION
                          Washington, D.C.  20549
                                     
                                     
                               SCHEDULE 13G
                                     
                                     
                 Under the Securities Exchange Act of 1934
            (Amendment No.                                  )*
                                     
                  American Power Conversion Corporation
                             (Name of Issuer)
                                     
                  Common Stock, $.01 par value per share
                      (Title of Class of Securities)
                                     
                               029066 10 7
                              (CUSIP Number)
     
     
     *The  remainder  of this cover page shall be  filled  out  for  a
     reporting  person's initial filing on this form with  respect  to
     the subject class of securities, and for any subsequent amendment
     containing information which would alter the disclosures provided
     in a prior cover page.
     
     The  information  required in the remainder of  this  cover  page
     shall  not be deemed to be "filed" for the purpose of Section  18
     of  the  Securities  Exchange Act of 1934  ("Act")  or  otherwise
     subject  to the liabilities of that section of the Act but  shall
     be  subject to all other provisions of the Act (however, see  the
     Notes).

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1  NAME OF REPORTING PERSON
   S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON
   American Power Conversion Corporation
   Employee Stock Ownership Plan
   
   
   
2  CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*
                                                  (a)
                                                  (b)
   
3  SEC USE ONLY
   
4  CITIZENSHIP OR PLACE OF ORGANIZATION
   
   Not Applicable
   
             5  SOLE VOTING POWER
                
                0  (See Item 4(c))
 NUMBER OF
  SHARES     6  SHARED VOTING POWER
BENEFICIALLY     
                4,844,774 (See Item 4(c))
 OWNED BY       
   EACH      7  SOLE DISPOSITIVE POWER
 REPORTING      
  PERSON        0
   WITH      8  SHARED DISPOSITIVE POWER
                
                4,844,774

9  AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
   
   4,844,774
   
10 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES*
 
   
11 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9
 
   5.1%
   
12 TYPE OF REPORTING PERSON *
 
   EP
   
                                     
                   *SEE INSTRUCTIONS BEFORE FILLING OUT!

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Item 1(a).     Name of Issuer:  American Power Conversion Corporation

Item 1(b).     Address of Issuer's Principal Executive Offices:
               P.O. Box 278, 132 Fairgrounds Road, West Kingston,
               Rhode Island 02892

Item 2(a).     Name of Person Filing:  American Power Conversion
               Corporation Employee Stock Ownership Plan

Item 2(b).     Address of Principal Business Office or, if None, Residence:
               American Power Conversion Corporation, P.O. Box 278,
               132 Fairgrounds Road, West Kingston, Rhode Island 02892

Item 2(c).     Citizenship:  Not Applicable

Item 2(d).     Title of Class of Securities:  Common Stock, $.01
               par value per share

Item 2(e).     CUSIP Number:  029066-10-7

Item 3.   If this statement is filed pursuant to Rule 13d-1(b),
          or 13d-2(b), check whether the person filing is a:

                    (a) [     ]    Broker or Dealer registered
                    under Section 15 of the Securities Exchange
                    Act of 1934 (the "Act").

                    (b) [     ]    Bank as defined in
                    Section 3(a)(6) of the Act.

                    (c) [     ]    Insurance Company as defined
                    in Section 3(a)(19) of the Act.

                    (d) [     ]    Investment Company registered
                    under Section 8 of the Investment Company Act
                    of 1940.

                    (e) [     ]    Investment Advisor registered
                    under Section 203 of the Investment Advisers
                    Act of 1940.

                    (f) [ X ] Employee Benefit Plan, Pension Fund
                    which is subject to the provisions of the
                    Employee Retirement Income Security Act of
                    1974 or Endowment Fund; see
                    Rule 13d-1(b)(1)(ii)(F) of the Act.

                    (g) [     ]    Parent Holding Company, in
                    accordance with Rule 13d-1(b)(ii)(G) of the
                    Act.

                    (h) [     ]    Group, in accordance with
                    Rule 13d-1(b)(1)(ii)(H) of the Act.

                    Not Applicable.

Item 4.        Ownership.

           (a) Amount Beneficially Owned: 4,844,774 shares.
          
           (b) Percent of Class:  5.1% (based on the 95,199,000
               shares of Common Stock reported to be outstanding
               on November 6, 1997 in the Quarterly Report on
               Form 10-Q of American Power Conversion Corporation
               for the quarter ended September 28, 1997).
       
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          (c)  Number of shares as to which such person has:

               (i)  sole power to vote or to direct the vote:  0 shares

               (ii) shared power to vote or to direct the vote:
                    4,844,774 shares

               (iii)     sole power to dispose or direct the disposition of:
                    0 shares

               (iv) shared power to dispose or to direct the disposition of:
                    4,844,774 shares

     The American Power Conversion Corporation Employee Stock
Ownership Plan Trust (the "Trust") was established pursuant to
the American Power Conversion Corporation Amended and Restated
Employee Stock Ownership Plan (the "ESOP").  Under the terms of
the ESOP, the Trustees must vote the allocated shares held in the
ESOP in accordance with the instructions of the participating
employees.  Any shares with respect to which voting instructions
have been sought but have not been timely received are not voted
by the Trustees.  Any shares with respect to which the Trustees
have the power to vote, but which have not been allocated to the
accounts of any participant, may be voted by the Trustees in the
same proportion as the Trustees are directed to vote the stock
with respect to which instructions have been received up to
twenty-four hours before commencement of any shareholder's
meeting.  As of December 31, 1997, 4,844,774 shares had been
allocated to participants' accounts and  no shares were
unallocated.

Item 5.   Ownership of Five Percent or Less of a Class.

          Not Applicable.

Item 6.   Ownership of More than Five Percent on Behalf of Another Person.

          Of the 4,844,774 shares reported as beneficially owned
          by the ESOP on this form, 4,844,774 shares have been
          allocated or are available for allocation to the
          accounts of certain employees and former employees of
          American Power Conversion Corporation in the ESOP.

Item 7.   Identification and Classification of the Subsidiary
          which Acquired the Security Being Reported on by the
          Parent Holding Company.

          Not Applicable.

Item 8.   Identification and Classification of Members of the
          Group.

          Not Applicable.

Item 9.   Notice of Dissolution of Group.

          Not Applicable.

Item 10.  Certification.

          By signing below I certify that, to the best of my
          knowledge and belief, the securities referred to above
          were acquired in the ordinary course of business and
          were not acquired for the purpose of and do not have
          the effect of changing or influencing the control of
          the issuer of such securities and were not acquired in
          connection with or as a participant in any transaction
          having such purpose or effect.

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                           SIGNATURES


     After reasonable inquiry and to the best of my knowledge and
belief, I certify that the information set forth in this
statement is true, complete and correct.



                                   AMERICAN POWER CONVERSION
                                   CORPORATION EMPLOYEE STOCK
                                   OWNERSHIP PLAN TRUST


February 13, 1998              By: /s/ Rodger B. Dowdell, Jr.
                                   --------------------------------   
                                   Rodger B. Dowdell, Jr., a Trustee






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