<PAGE>
 
             As filed with the Securities and Exchange Commission
                              on October 13, 1995


                                                 Registration No. 33-

                      SECURITIES AND EXCHANGE COMMISSION
                            Washington, D.C. 20549

                                   FORM S-8

                         REGISTRATION STATEMENT UNDER
                          THE SECURITIES ACT OF 1933

                             Sequoia Systems, Inc.
- --------------------------------------------------------------------------------
              (Exact name of issuer as specified in its charter)

           Delaware                                              04-2738973     
- -------------------------------                              -------------------
(State or other jurisdiction of                               (I.R.S. Employer
 incorporation or organization)                              Identification No.)

                              400 Nickerson Road
                       Marlborough, Massachusetts 01752
- --------------------------------------------------------------------------------
      (Address of Principal Executive Offices)     (Zip Code)

                       1993 Employee Stock Purchase Plan
                       ---------------------------------
                           (Full title of the plan)

                             Jeremy F. Swett, Esq.
                              400 Nickerson Road
                       Marlborough, Massachusetts  01752
- --------------------------------------------------------------------------------
                    (Name and address of agent for service)

                                (508) 480-0800
- --------------------------------------------------------------------------------
         (Telephone number, including area code, of agent for service)

                    CALCULATION OF REGISTRATION FEE
<TABLE> 
<CAPTION> 
- ------------------------------------------------------------------------------
 Title of                        Proposed          Proposed      
securities     Amount to         maximum           maximum         Amount of
  to be            be         offering price      aggregate       registration
registered     registered       per share       offering price        fee     
- ----------     ----------     --------------    --------------    ------------
<S>            <C>            <C>               <C>               <C> 
Common         500,000         $5.94(1)          $2,970,000(1)      $1,025.00
Stock,          shares                                           
$.40 par
value
</TABLE> 
- -------------

(1)  Estimated solely for the purpose of calculating the registration fee
pursuant to Rule 457(c) and Rule 457(h) under the Securities Act of 1933, as
amended, upon the basis of the average of the high and low prices of the
Registrant's Common Stock as reported on the Nasdaq National Market on October
10, 1995.


                              Page 1 of 6 pages.
                        Exhibit Index begins on page 4.
<PAGE>
 
                    Statement of Incorporation by Reference


     Pursuant to General Instruction E to Form S-8, this Registration Statement
on Form S-8 (the "Registration Statement") incorporates by reference the
contents of the Registration Statement on Form S-8, filed by Sequoia Systems,
Inc., a Delaware corporation (the "Registrant"), with the Securities and
Exchange Commission on September 18, 1993 (File No. 33-64690) relating to the
Registrant's 1993 Employee Stock Purchase Plan.

                                  SIGNATURES


     Pursuant to the requirements of the Securities Act of 1933, 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 Town of Marlborough, Commonwealth of Massachusetts, on this
30th day of September, 1995.

                                      SEQUOIA SYSTEMS, INC.



                                      By:  /s/Richard B. Goldman
                                           ---------------------
                                           Richard B. Goldman
                                           Vice President and Chief
                                             Financial Officer




                               POWER OF ATTORNEY


     We, the undersigned officers and directors of Sequoia Systems, Inc., hereby
severally constitute Cornelius P. McMullan, Richard B. Goldman, Jeremy F. Swett
and David A. Westenberg and each of them singly, our true and lawful attorneys
with full power to any of them, and to 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 amendments to said Registration
Statement and generally to do all such things in our name and behalf in our
capacities as officers and directors to enable Sequoia Systems, Inc. to comply
with the provisions of the Securities Act of 1933, as amended, and all
requirements of the Securities and Exchange Commission, hereby ratifying and
confirming our signatures as they may be signed by our said attorneys, or any of
them, to said Registration Statement and any and all amendments thereto.

                                        - 2 -
<PAGE>
 
     Pursuant to the requirements of the Securities Act of 1933, this
Registration Statement has been signed by the following persons in the
capacities and on the dates indicated.

Signature                       Title                         Date
- ---------                       -----                         ----
                                                    
/s/Cornelius P. McMullan        President, Chief         )September 30, 1995
- ------------------------        Executive Officer        )
Cornelius P. McMullan           and Director             )
                                (Principal Executive     )
                                Officer)                 )
                                                         )
                                                         )
/s/Richard B. Goldman           Vice President,          )September 30, 1995  
- ---------------------           Finance and Chief        )    
Richard B. Goldman              Financial Officer        )
                                and (Principal           )   
                                Accounting Officer)      )
                                                         )
                                                         )
/s/Dean C. Campbell             Director                 )September 30, 1995
- -------------------                                      ) 
Dean C. Campbell                                         )
                                                         )
/s/A. Theodore Engkvist         Director                 )September 30, 1995
- -----------------------                                  )    
A. Theodore Engkvist                                     )
                                                         )
/s/Francis J. Hughes, Jr.       Director                 )September 30, 1995
- -------------------------                                )
Francis J. Hughes, Jr.                                   )
                                                         )
                                Director                 )September __, 1995
- ----------------                                         )
Dennis Malloy                                            )
                                                         )
/s/John F. Smith                Director                 )September 30, 1995
- ----------------                                         )    
John F. Smith                                            )
                                                         )
/s/J. Michael Stewart           Director                 )September 30, 1995
- ---------------------               
J. Michael Stewart                  


                                         -3-
<PAGE>
 
                                 EXHIBIT INDEX
                                 -------------

                                                               Sequential
Exhibit                                                         Page No.
- -------                                                        ----------
                                                        
 4.1      Specimen certificate representing the Common        
          Stock filed as Exhibit 4.1 to the Registrant's      
          Registration Statement on Form S-1 (File No.        
          33-33024) and incorporated herein by                
          this reference                                           --
                                                        
 5.1      Opinion of Hale and Dorr                                  5
                                                        
23.1      Consent of Hale and Dorr                            
          (included in Exhibit 5.1)                                --
                                                        
23.2      Consent of Coopers & Lybrand L.L.P.                       6
                                                        
24.1      Power of Attorney (included in the                  
          signature pages of this Registration                     --
          Statement)
[{"type": "S-8", "sequence": "1", "description": "FORM S-8", "secsgml_size_bytes": 9595}]
{"company-data": {"conformed-name": "SEQUOIA SYSTEMS INC", "cik": "0000724621", "assigned-sic": "7373", "irs-number": "042738973", "state-of-incorporation": "DE", "fiscal-year-end": "0630"}, "filing-values": {"form-type": "S-8", "act": "33", "file-number": "033-63407", "film-number": "95580563"}, "business-address": {"street1": "400 NICKERSON RD", "city": "MARLBORO", "state": "MA", "zip": "01752", "phone": "5084800800"}, "mail-address": {"street1": "400 NICKERSON ROAD", "city": "MARLBORO", "state": "MA", "zip": "01752"}}
As filed with the Securities and Exchange Commission
                              on October 13, 1995

                                                 Registration No. 33-

                      SECURITIES AND EXCHANGE COMMISSION
                            Washington, D.C. 20549

                                   FORM S-8

                         REGISTRATION STATEMENT UNDER
                          THE SECURITIES ACT OF 1933

                             Sequoia Systems, Inc.
- --------------------------------------------------------------------------------
              (Exact name of issuer as specified in its charter)

           Delaware                                              04-2738973     
- -------------------------------                              -------------------
(State or other jurisdiction of                               (I.R.S. Employer
 incorporation or organization)                              Identification No.)

                              400 Nickerson Road
                       Marlborough, Massachusetts 01752
- --------------------------------------------------------------------------------
      (Address of Principal Executive Offices)     (Zip Code)

                       1993 Employee Stock Purchase Plan
                       ---------------------------------
                           (Full title of the plan)

                             Jeremy F. Swett, Esq.
                              400 Nickerson Road
                       Marlborough, Massachusetts  01752
- --------------------------------------------------------------------------------
                    (Name and address of agent for service)

                                (508) 480-0800
- --------------------------------------------------------------------------------
         (Telephone number, including area code, of agent for service)

                    CALCULATION OF REGISTRATION FEE
- ------------------------------------------------------------------------------
 Title of                        Proposed          Proposed      
securities     Amount to         maximum           maximum         Amount of
  to be            be         offering price      aggregate       registration
registered     registered       per share       offering price        fee     
- ----------     ----------     --------------    --------------    ------------
Common         500,000         $5.94(1)          $2,970,000(1)      $1,025.00
Stock,          shares                                           
$.40 par
value
- -------------

(1)  Estimated solely for the purpose of calculating the registration fee
pursuant to Rule 457(c) and Rule 457(h) under the Securities Act of 1933, as
amended, upon the basis of the average of the high and low prices of the
Registrant's Common Stock as reported on the Nasdaq National Market on October
10, 1995.

                              Page 1 of 6 pages.
                        Exhibit Index begins on page 4.
Statement of Incorporation by Reference

     Pursuant to General Instruction E to Form S-8, this Registration Statement
on Form S-8 (the "Registration Statement") incorporates by reference the
contents of the Registration Statement on Form S-8, filed by Sequoia Systems,
Inc., a Delaware corporation (the "Registrant"), with the Securities and
Exchange Commission on September 18, 1993 (File No. 33-64690) relating to the
Registrant's 1993 Employee Stock Purchase Plan.

                                  SIGNATURES

     Pursuant to the requirements of the Securities Act of 1933, 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 Town of Marlborough, Commonwealth of Massachusetts, on this
30th day of September, 1995.

                                      SEQUOIA SYSTEMS, INC.

                                      By:  /s/Richard B. Goldman
                                           ---------------------
                                           Richard B. Goldman
                                           Vice President and Chief
                                             Financial Officer

                               POWER OF ATTORNEY

     We, the undersigned officers and directors of Sequoia Systems, Inc., hereby
severally constitute Cornelius P. McMullan, Richard B. Goldman, Jeremy F. Swett
and David A. Westenberg and each of them singly, our true and lawful attorneys
with full power to any of them, and to 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 amendments to said Registration
Statement and generally to do all such things in our name and behalf in our
capacities as officers and directors to enable Sequoia Systems, Inc. to comply
with the provisions of the Securities Act of 1933, as amended, and all
requirements of the Securities and Exchange Commission, hereby ratifying and
confirming our signatures as they may be signed by our said attorneys, or any of
them, to said Registration Statement and any and all amendments thereto.

                                        - 2 -
Pursuant to the requirements of the Securities Act of 1933, this
Registration Statement has been signed by the following persons in the
capacities and on the dates indicated.

Signature                       Title                         Date
- ---------                       -----                         ----
                                                    
/s/Cornelius P. McMullan        President, Chief         )September 30, 1995
- ------------------------        Executive Officer        )
Cornelius P. McMullan           and Director             )
                                (Principal Executive     )
                                Officer)                 )
                                                         )
                                                         )
/s/Richard B. Goldman           Vice President,          )September 30, 1995  
- ---------------------           Finance and Chief        )    
Richard B. Goldman              Financial Officer        )
                                and (Principal           )   
                                Accounting Officer)      )
                                                         )
                                                         )
/s/Dean C. Campbell             Director                 )September 30, 1995
- -------------------                                      ) 
Dean C. Campbell                                         )
                                                         )
/s/A. Theodore Engkvist         Director                 )September 30, 1995
- -----------------------                                  )    
A. Theodore Engkvist                                     )
                                                         )
/s/Francis J. Hughes, Jr.       Director                 )September 30, 1995
- -------------------------                                )
Francis J. Hughes, Jr.                                   )
                                                         )
                                Director                 )September __, 1995
- ----------------                                         )
Dennis Malloy                                            )
                                                         )
/s/John F. Smith                Director                 )September 30, 1995
- ----------------                                         )    
John F. Smith                                            )
                                                         )
/s/J. Michael Stewart           Director                 )September 30, 1995
- ---------------------               
J. Michael Stewart                  

                                         -3-
EXHIBIT INDEX
                                 -------------

                                                               Sequential
Exhibit                                                         Page No.
- -------                                                        ----------
                                                        
 4.1      Specimen certificate representing the Common        
          Stock filed as Exhibit 4.1 to the Registrant's      
          Registration Statement on Form S-1 (File No.        
          33-33024) and incorporated herein by                
          this reference                                           --
                                                        
 5.1      Opinion of Hale and Dorr                                  5
                                                        
23.1      Consent of Hale and Dorr                            
          (included in Exhibit 5.1)                                --
                                                        
23.2      Consent of Coopers & Lybrand L.L.P.                       6
                                                        
24.1      Power of Attorney (included in the                  
          signature pages of this Registration                     --
          Statement)