EXHIBIT 5.1

                                 August 12, 2002

Sun Microsystems, Inc.
4150 Network Circle
Santa Clara, CA 95054

        RE:  REGISTRATION STATEMENT ON FORM S-8

Ladies and Gentlemen:

        We have acted as counsel to Sun Microsystems, Inc., a Delaware
corporation (the "COMPANY") and have examined the Registration Statement on Form
S-8 (the "REGISTRATION STATEMENT") to be filed by the Company with the
Securities and Exchange Commission on or about August 12, 2002 in connection
with the registration under the Securities Act of 1933, as amended (the "1933
Act") of 209,648 shares of the Company's Common Stock, par value $0.00067 per
share (the "SHARES"), reserved for issuance under the Afara WebSystems, Inc.
2000 Equity Incentive Plan (the "PLAN").

        As your legal counsel, we have examined the Restated Certificate of
Incorporation and Bylaws of the Company, the Plan and such other documents of
the Company as we have deemed necessary or appropriate for the purposes of the
opinion expressed herein, and are familiar with the proceedings proposed to be
taken by the Company in connection with the operation and administration of the
Plan and the sale and issuance of the Shares pursuant to the Plan.

        It is our opinion that the Shares, when issued and sold in the manner
referred to in the Plan and pursuant to the agreements which accompany the Plan,
will be legally and validly issued, fully paid and nonassessable.

        We consent to the use of this opinion as an Exhibit to the Registration
Statement and further consent to the use of our name wherever appearing in the
Registration Statement and any subsequent amendment thereto.

                                          Very truly yours,

                                          WILSON SONSINI GOODRICH & ROSATI
                                          Professional Corporation

                                          /s/ Wilson Sonsini Goodrich & Rosati