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                                                                     EXHIBIT 3.5


   STATE OF DELAWARE
  SECRETARY OF STATE
DIVISION OF CORPORATIONS
FILED 09:00 AM 05/11/2000
  001240117 -- 2290402


                            CERTIFICATE OF AMENDMENT
                                     OF THE
                          CERTIFICATE OF INCORPORATION
                                       OF
                            MRV COMMUNICATIONS, INC.

        MRV Communications, Inc., a corporation organized and existing under the
laws of the State of Delaware (the "Corporation"), pursuant to the provisions of
the General Corporation Law of the State of Delaware (the "DGCL"), DOES HEREBY
CERTIFY as follows:

        FIRST: The Certificate of Incorporation of the Company is hereby amended
by deleting paragraphs A and B of Section 4 of the Certificate of Incorporation
in their present form and substituting therefor new paragraphs A and B of
Section 4 in the following form:

        A. This corporation is authorized to issue two classes of stock, to be
designated, respectively, "Common Stock" and "Preferred Stock." The total number
of shares of this corporation is authorized to issue is One Hundred Sixty One
Million (161,000,000) shares of capital stock.

        B. Of such authorized shares, One Hundred Sixty Million (160,000,000)
shares shall be designated "Common Stock" and have a par value of $.0017 per
share. One Million (1,000,000) shares shall be designated "Preferred Stock" and
have a par value of $0.01 per share. Upon the filing of this Certificate of
Amendment of the Certificate of Incorporation, each share of Common Stock of the
corporation outstanding immediately prior to such filing shall be reconstituted
as and converted into two shares of Common Stock.

        SECOND: The amendment to the Certificate of Incorporation of the
Corporation set forth in this Certificate of Amendment has been duly adopted in
accordance with the provisions of Section 242 of the DGCL by (a) the Board of
Directors of the Corporation having duly adopted a resolution setting forth such
amendment and declaring its advisability and submitting it to the stockholders
of the Corporation for their approval, and (b) the stockholders of the
Corporation having duly adopted such amendment by vote of the holders of a
majority of the outstanding stock entitled to vote thereon at a special meeting
of stockholders called and held upon notice in accordance with Section 222 of
the DGCL.

        IN WITNESS WHEREOF, the Corporation has caused its corporate seal to be
hereunto affixed and this Certificate of Amendment to be signed by Noam Lotan,
its President and Chief Executive Officer, and attested by Shlomo Margalit, its
Secretary, this 10th day of May 2000.


                                        MRV COMMUNICATIONS, INC.


                                        By: /s/ NOAM LOTAN
                                           -------------------------------------
                                           Noam Lotan
                                           President and Chief Executive Officer



ATTEST:


 /s/ SHLOMO MARGALIT
---------------------------
Shlomo Margalit
Secretary