<PAGE>
 
             As filed with the Securities and Exchange Commission
                                on June 6, 1997

                                         Registration No. 333-_____
================================================================================


                      SECURITIES AND EXCHANGE COMMISSION
                            Washington, D. C. 20549

                                   FORM S-8

                         REGISTRATION STATEMENT UNDER
                          THE SECURITIES ACT OF 1933

                          BANYAN SYSTEMS INCORPORATED
            (Exact name of registrant as specified in its charter)


      MASSACHUSETTS                                       04-2798394
(State or other jurisdiction of                       (I.R.S. Employer
 incorporation or organization)                    Identification Number)

120 FLANDERS ROAD, WESTBORO, MASSACHUSETTS                     01581
 (Address of Principal Executive Offices)                   (Zip Code)

                        1992 DIRECTOR STOCK OPTION PLAN
                           (Full title of the plan)

                             MARK G. BORDEN, ESQ.
                               HALE AND DORR LLP
                                60 STATE STREET
                          BOSTON, MASSACHUSETTS 02109
                    (Name and address of agent for service)

                                (617) 526-6000
         (Telephone number, including area code, of agent for service)

<TABLE> 
<CAPTION> 
==================================================================================================

                        CALCULATION OF REGISTRATION FEE

                                        Proposed             Proposed          
                                        maximum              maximum       
Title of securities    Amount to be     offering price per   aggregate         Amount of
to be registered       registered       share                offering price    registration fee
----------------       ----------       -----------------    --------------    -----------------
<S>                  <C>              <C>                   <C>               <C>
Common Stock          100,000 shares    $1.78125(1)             $178,125(1)        $54
 $.01 par value
--------------------------------------------------------------------------------------------------
</TABLE>


(1)  Estimated solely for the purpose of calculating the registration fee, and
     based upon the average of the high and low prices of the Common Stock on
     the Nasdaq National Market on June 4, 1997 in accordance with Rules 457(c)
     and 457(h) of the Securities Act of 1933.

================================================================================
<PAGE>
 
                    Statement of Incorporation by Reference
                    ---------------------------------------

     This Registration Statement on Form S-8 incorporates by reference the
contents of (i) PART I and (ii) PART II, Items 3, 4, 6, 7, 8 and 9, of the
Registration Statement on Form S-8, File No. 33-50864, filed by the Registrant
on August 14, 1992 relating to the Registrant's 1992 Director Stock Option Plan.


     Item 5.  Interests of Named Experts and Counsel
              --------------------------------------

     Not applicable.
<PAGE>
 
                                   SIGNATURES

     Pursuant to the requirements of the Securities Act, 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 Westboro, Massachusetts on the 5th day of June, 1997.

 
                                    BANYAN SYSTEMS INCORPORATED



                                    By:  /s/ William P. Ferry
                                       ----------------------
                                         William P. Ferry
                                         President and
                                         Chief Executive Officer



                               POWER OF ATTORNEY

     We, the undersigned officers and directors of Banyan Systems Incorporated,
hereby severally constitute William P. Ferry, Richard M. Spaulding and Mark G.
Borden, and each of them singly, our true and lawful attorneys with full power
to them, and each of them singly, to sign for us and in our names in the
capacities indicated below, the Registration Statement on Form S-8 filed
herewith and any and all subsequent amendments to said Registration Statement,
and generally to do all such things in our names and behalf in our capacities as
officers and directors to enable Banyan Systems Incorporated to comply with all
requirements of the Securities and Exchange Commission, hereby ratifying and
confirming our signatures as they may be signed by said attorneys, or any of
them, to said Registration Statement and any and all amendments thereto.
<PAGE>
 
     Pursuant to the requirements of the Securities Act, this Registration
Statement has been signed below by the following persons in the capacities and
on the dates indicated.

<TABLE> 
<CAPTION> 

     Signature                      Title                           Date
     ---------                      -----                           ----
 
<S>                            <C>                               <C> 
/s/ William P. Ferry            President, Chief Executive          June 5, 1997
-----------------------------   Officer and Director (Principal
William P. Ferry                Executive Officer)

 
/s/ Richard M. Spaulding        Vice President, Finance             June 5, 1997
-----------------------------   and Treasurer (Principal
Richard M. Spaulding            Financial Officer and 
                                Principal Accounting Officer) 
                               
 
 
/s/ G. Leonard Baker, Jr.       Director                            June 5, 1997
-----------------------------
G. Leonard Baker, Jr.
 
/s/ John F. Burton              Director                            June 5, 1997
-----------------------------
John F. Burton
 
/s/ A. Peter Hamilton           Director                            June 5, 1997
-----------------------------
A. Peter Hamilton
 
                                Director                           
-----------------------------
David C. Mahoney
 
/s/ Fontaine K. Richardson      Director                            June 5, 1997
-----------------------------
Fontaine K. Richardson
 
/s/ David N. Strohm             Director                            June 5, 1997
-----------------------------
David N. Strohm
</TABLE>
<PAGE>
 
                                 EXHIBIT INDEX
                                 -------------


Exhibit
Number      Description
-------     -----------

   5.1      Opinion of Hale and Dorr LLP

  23.1      Consent of Hale and Dorr LLP (included in Exhibit 5.1)

  23.2      Consent of Coopers & Lybrand L.L.P.

  24.1      Power of Attorney (included on the signature
            page of this Registration Statement)
[{"type": "S-8", "sequence": "1", "description": "FORM S-8", "secsgml_size_bytes": 7188}]
{"company-data": {"conformed-name": "BANYAN SYSTEMS INC", "cik": "0000888711", "assigned-sic": "7372", "irs-number": "042798394", "state-of-incorporation": "MA", "fiscal-year-end": "1231"}, "filing-values": {"form-type": "S-8", "act": "33", "file-number": "333-28675", "film-number": "97620368"}, "business-address": {"street1": "120 FLANDERS ROAD", "city": "WESTBORO", "state": "MA", "zip": "01581", "phone": "5088981000"}}
As filed with the Securities and Exchange Commission
                                on June 6, 1997

                                         Registration No. 333-_____
================================================================================

                      SECURITIES AND EXCHANGE COMMISSION
                            Washington, D. C. 20549

                                   FORM S-8

                         REGISTRATION STATEMENT UNDER
                          THE SECURITIES ACT OF 1933

                          BANYAN SYSTEMS INCORPORATED
            (Exact name of registrant as specified in its charter)

      MASSACHUSETTS                                       04-2798394
(State or other jurisdiction of                       (I.R.S. Employer
 incorporation or organization)                    Identification Number)

120 FLANDERS ROAD, WESTBORO, MASSACHUSETTS                     01581
 (Address of Principal Executive Offices)                   (Zip Code)

                        1992 DIRECTOR STOCK OPTION PLAN
                           (Full title of the plan)

                             MARK G. BORDEN, ESQ.
                               HALE AND DORR LLP
                                60 STATE STREET
                          BOSTON, MASSACHUSETTS 02109
                    (Name and address of agent for service)

                                (617) 526-6000
         (Telephone number, including area code, of agent for service)
==================================================================================================

                        CALCULATION OF REGISTRATION FEE

                                        Proposed             Proposed          
                                        maximum              maximum       
Title of securities    Amount to be     offering price per   aggregate         Amount of
to be registered       registered       share                offering price    registration fee
----------------       ----------       -----------------    --------------    -----------------
Common Stock          100,000 shares    $1.78125(1)             $178,125(1)        $54
 $.01 par value
--------------------------------------------------------------------------------------------------
(1)  Estimated solely for the purpose of calculating the registration fee, and
     based upon the average of the high and low prices of the Common Stock on
     the Nasdaq National Market on June 4, 1997 in accordance with Rules 457(c)
     and 457(h) of the Securities Act of 1933.

================================================================================
Statement of Incorporation by Reference
                    ---------------------------------------

     This Registration Statement on Form S-8 incorporates by reference the
contents of (i) PART I and (ii) PART II, Items 3, 4, 6, 7, 8 and 9, of the
Registration Statement on Form S-8, File No. 33-50864, filed by the Registrant
on August 14, 1992 relating to the Registrant's 1992 Director Stock Option Plan.

     Item 5.  Interests of Named Experts and Counsel
              --------------------------------------

     Not applicable.
SIGNATURES

     Pursuant to the requirements of the Securities Act, 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 Westboro, Massachusetts on the 5th day of June, 1997.

 
                                    BANYAN SYSTEMS INCORPORATED

                                    By:  /s/ William P. Ferry
                                       ----------------------
                                         William P. Ferry
                                         President and
                                         Chief Executive Officer

                               POWER OF ATTORNEY

     We, the undersigned officers and directors of Banyan Systems Incorporated,
hereby severally constitute William P. Ferry, Richard M. Spaulding and Mark G.
Borden, and each of them singly, our true and lawful attorneys with full power
to them, and each of them singly, to sign for us and in our names in the
capacities indicated below, the Registration Statement on Form S-8 filed
herewith and any and all subsequent amendments to said Registration Statement,
and generally to do all such things in our names and behalf in our capacities as
officers and directors to enable Banyan Systems Incorporated to comply with all
requirements of the Securities and Exchange Commission, hereby ratifying and
confirming our signatures as they may be signed by said attorneys, or any of
them, to said Registration Statement and any and all amendments thereto.
Pursuant to the requirements of the Securities Act, this Registration
Statement has been signed below by the following persons in the capacities and
on the dates indicated.
Signature                      Title                           Date
     ---------                      -----                           ----
/s/ William P. Ferry            President, Chief Executive          June 5, 1997
-----------------------------   Officer and Director (Principal
William P. Ferry                Executive Officer)

 
/s/ Richard M. Spaulding        Vice President, Finance             June 5, 1997
-----------------------------   and Treasurer (Principal
Richard M. Spaulding            Financial Officer and 
                                Principal Accounting Officer) 
                               
 
 
/s/ G. Leonard Baker, Jr.       Director                            June 5, 1997
-----------------------------
G. Leonard Baker, Jr.
 
/s/ John F. Burton              Director                            June 5, 1997
-----------------------------
John F. Burton
 
/s/ A. Peter Hamilton           Director                            June 5, 1997
-----------------------------
A. Peter Hamilton
 
                                Director                           
-----------------------------
David C. Mahoney
 
/s/ Fontaine K. Richardson      Director                            June 5, 1997
-----------------------------
Fontaine K. Richardson
 
/s/ David N. Strohm             Director                            June 5, 1997
-----------------------------
David N. Strohm
EXHIBIT INDEX
                                 -------------

Exhibit
Number      Description
-------     -----------

   5.1      Opinion of Hale and Dorr LLP

  23.1      Consent of Hale and Dorr LLP (included in Exhibit 5.1)

  23.2      Consent of Coopers & Lybrand L.L.P.

  24.1      Power of Attorney (included on the signature
            page of this Registration Statement)