===============================================================================
                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549

                                  SCHEDULE 13D
                                 (Rule 13d-101)

                                (Amendment No. 4)
                                 OPTIBASE, LTD.
                                (Name of Issuer)

          ORDINARY SHARES                                          M7524R108
 NOMINAL VALUE NIS 0.13 PER SHARE
  (Title of class of securities)                                  (CUSIP number)

                              DAVID P. STONE, ESQ.
                           WEIL, GOTSHAL & MANGES LLP
                                767 FIFTH AVENUE
                               NEW YORK, NY 10153

                  (Name, address and telephone number of person
               authorized to receive notices and communications)


                                DECEMBER 23, 2002
             (Date of event which requires filing of this statement)


If the filing person has previously filed a statement on Schedule 13G to report
the acquisition that is the subject of this Schedule 13D, and is filing this
schedule because of Rule 13d-1(e), 13d-1(f) or 13d-1(g), check the following box
[_].

Note: Schedules filed in paper format shall include a signed original and five
copies of the schedule, including all Exhibits. See Rule 13d-7 for other parties
to whom copies are to be sent.

                         (Continued on following pages)
                               (Page 1 of 6 Pages)

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----------------------------------- ---------------------------------------------- -------------- ----------------------------------
CUSIP No.                           M7524R108                                           13D                              Page 2 of 6
----------------------------------- ---------------------------------------------- -------------- ----------------------------------

                                                                                                                 
------------------------------------------------------------------------------------------------------------------------------------
          1            NAME OF REPORTING PERSON:                                   MOSHE NAMDAR
                       I.R.S. IDENTIFICATION NO.                                        N/A
                       OF ABOVE PERSON (ENTITIES ONLY):
---------------------- -------------------------------------------------------------------------------------------------------------
          2            CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP:                                                    (A) [X]
                                                                                                                            (B) [_]
---------------------- -------------------------------------------------------------------------------------------------------------
          3            SEC USE ONLY
---------------------- ------------------------------------- -----------------------------------------------------------------------
          4            SOURCE OF FUNDS:                        PF
---------------------- -------------------------------------------------------------------------------------------------------------
          5            CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEM 2(d) OR 2(e):                  [_]
---------------------- -------------------------------------------------------------------------- ----------------------------------
          6            CITIZENSHIP OR PLACE OF ORGANIZATION:                    ISRAELI
----------------------------------- -------- ---------------------------------------------------- ----------------------------------
            NUMBER OF                  7     SOLE VOTING POWER:                                   1,070,000
              SHARES
                                    -------- ---------------------------------------------------- ----------------------------------
           BENEFICIALLY                8     SHARED VOTING POWER:
             OWNED BY
                                    -------- ---------------------------------------------------- ----------------------------------
               EACH                    9     SOLE DISPOSITIVE POWER:                              1,070,000
            REPORTING
                                    -------- ---------------------------------------------------- ----------------------------------
           PERSON WITH                10     SHARED DISPOSITIVE POWER:

---------------------- -------------------------------------------------------------------------- ----------------------------------
         11            AGGREGATE AMOUNT BENEFICIALLY OWNED BY REPORTING PERSON:                   1,964,300 (1)
---------------------- -------------------------------------------------------------------------------------------------------------
         12            CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES:                                   [ ]
---------------------- -------------------------------------------------------------------------------------------------------------
         13            PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11):                                            16.01%
---------------------- -------------------------------------------------------------------------- ----------------------------------
         14            TYPE OF REPORTING PERSON:                                IN
---------------------- -------------------------------------------------------------------------- ----------------------------------


-------------------
(1) Mr. Moshe Namdar disclaims beneficial ownership of all ordinary shares that are owned, may be owned or deemed owned by
Mr. Avraham Namdar





----------------------------------- ---------------------------------------------- -------------- ----------------------------------
CUSIP No.                           M7524R108                                           13D                              Page 3 of 6
----------------------------------- ---------------------------------------------- -------------- ----------------------------------


------------------------------------------------------------------------------------------------------------------------------------
          1            NAME OF REPORTING PERSON:                                   AVRAHAM NAMDAR
                       I.R.S. IDENTIFICATION NO.                                          N/A
                       OF ABOVE PERSON (ENTITY ONLY):
---------------------- -------------------------------------------------------------------------------------------------------------
          2            CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP:                                                    (A) [X]
                                                                                                                            (B) [_]
---------------------- -------------------------------------------------------------------------------------------------------------
          3            SEC USE ONLY
---------------------- ------------------------------------- -----------------------------------------------------------------------
          4            SOURCE OF FUNDS:                      PF
---------------------- -------------------------------------------------------------------------------------------------------------
          5            CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEM 2(d) OR 2(e):                  [_]
---------------------- ----------------------------------------------------------- -------------------------------------------------
          6            CITIZENSHIP OR PLACE OF ORGANIZATION:                    ISRAELI
----------------------------------- -------- ---------------------------------------------------- ----------------------------------
            NUMBER OF                  7     SOLE VOTING POWER:                                   894,300
              SHARES
                                    -------- ---------------------------------------------------- ----------------------------------
           BENEFICIALLY                8     SHARED VOTING POWER:
             OWNED BY
                                    -------- ---------------------------------------------------- ----------------------------------
               EACH                    9     SOLE DISPOSITIVE POWER:                              894,300
            REPORTING
                                    -------- ---------------------------------------------------- ----------------------------------
           PERSON WITH                10     SHARED DISPOSITIVE POWER:

---------------------- -------------------------------------------------------------------------- ----------------------------------
         11            AGGREGATE AMOUNT BENEFICIALLY OWNED BY REPORTING PERSON:                   1, 964,300 (1)
---------------------- -------------------------------------------------------------------------------------------------------------
         12            CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES:                                   [ ]
---------------------- -------------------------------------------------------------------------------------------------------------
         13            PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11):                                            16.01%
---------------------- ----------------------------------------------------------- -------------------------------------------------
         14            TYPE OF REPORTING PERSON:                                IN
---------------------- ----------------------------------------------------------- -------------------------------------------------


-------------------
(1) Mr. Avraham Namdar disclaims beneficial ownership of all ordinary shares that are owned, may be owned or deemed owned by
Mr. Moshe Namdar





--------------------------------------------------------------------------------
CUSIP No.              M7524R108           13D                       Page 4 of 6
--------------------------------------------------------------------------------

ITEM 1.   SECURITY AND ISSUER

              This Amendment No. 4 ("Amendment No. 4") amends and supplements
the statement on Schedule 13D filed on July 24, 2002 (the "Statement"), as
amended and supplemented by Amendment No. 1, filed on August 1, 2002 and
Amendment No. 2, filed on October 3, 2002 and Amendment No. 3, filed on November
25, 2002 relating to Ordinary Shares, par value NIS 0.13 per share (the
"Ordinary Shares"), of Optibase Ltd., a corporation organized under the laws of
Israel (the "Issuer") filed on behalf of Messrs. Moshe and Avraham Mandar
(collectively, the "Reporting Persons").

ITEM 3.   SOURCE AND AMOUNT OF FUNDS OR OTHER CONSIDERATION

              As of the date hereof, the Reporting Persons purchased an
aggregate of 1,964,300 Ordinary Shares for total consideration (including
brokerage commissions) of $5,448,933. Such shares were purchased with the
Reporting Person's personal funds.

ITEM 5.   INTEREST IN SECURITIES OF THE ISSUER

(a)  Mr. Moshe Namdar and Mr. Avraham Namdar are brothers. As a result, each of
the Reporting Persons may be deemed to beneficially own 1,964,300 Ordinary
Shares, or approximately 16.01% of the total outstanding Ordinary Shares (based
on the number of the Issuer's Ordinary Shares outstanding as of October 27,
2002, of 12,268,596, as stated in the Issuer's report on form 6-K, filed with
the Securities and Exchange Commission on December 20, 2002).

(b)  Mr. Moshe Namdar has the power to vote or direct the vote and dispose or
direct the disposition of 940,000 Ordinary Shares covered by this Schedule 13D.

     Mr. Avraham Namdar has the power to vote or direct the vote and
dispose or direct the disposition of 894,300 Ordinary Shares covered by this
Schedule 13D.

(c)  Transactions in the Ordinary Shares effected by the Reporting Persons since
November 13, 2002 are described in Schedule A attached hereto and incorporated
herein by reference. All such transactions were effected in the open market on
the Nasdaq National Market.

(d), (e)   Not applicable.


ITEM 7.  MATERIAL TO BE FILED AS EXHIBITS

Exhibit No.          Description
-----------          -----------


Schedule A           Information concerning transactions in the Ordinary Shares
                     effected by the Reporting Persons






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CUSIP No.              M7524R108           13D                       Page 5 of 6
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SIGNATURE

           After reasonable inquiry and to the best of my knowledge and belief,
I certify that the information set forth in this Amendment No. 4 is true,
complete and correct.

December 29, 2002

                                                    Moshe Namdar


                                                    /s/ Moshe Namdar
                                                    ----------------------------



                                                    Avraham Namdar


                                                    /s/ Avraham Namdar
                                                    ----------------------------






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CUSIP No.              M7524R108           13D                       Page 6 of 6
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                                   SCHEDULE A

                 Schedule of Transactions in the Ordinary Shares

       Date of          Number of                Price per        Nature of
     Transaction         Shares                    Share         Transaction
     -----------         ------                    -----         -----------


      11/26/02           80,000          $         1.77            Purchase (1)
      12/23/02           50,000          $         2.00            Purchase (1)






--------
(1) - Purchase by Mr. Moshe Namdar