Filed Pursuant to Rule 424(b)(3)
                                                      Registration No. 333-68062

                           Prospectus Supplement No. 3
                      To Prospectus dated September 6, 2001

                                  $175,000,000

                             Brooks Automation, Inc.

                4.75% Convertible Subordinated Notes Due 2008 and
             the Common Stock Issuable Upon Conversion of the Notes


     This prospectus supplement no. 3 relates to the resale by the selling
securityholders of 4.75% convertible subordinated notes due June 1, 2008, of
Brooks Automation, Inc. and the shares of common stock, $.01 par value, of
Brooks Automation, Inc. issuable upon the conversion of the notes.

     This prospectus supplement should be read in conjunction with the
prospectus dated September 6, 2001, the prospectus supplement no. 1 dated
September 19, 2001 and the prospectus supplement no. 2 dated September 27, 2001,
which are to be delivered with this prospectus supplement no. 3. All capitalized
terms used but not defined in this prospectus supplement no. 3 shall have the
meaning given them in the prospectus.

     The following table contains information as of October 23, 2001, with
respect to certain selling securityholders and the principal amount of notes and
underlying common stock beneficially owned by each of the selling
securityholders listed herein that may be offered using this prospectus. The
information is based on information provided by or on behalf of the selling
securityholders and may have changed as of the date hereof. Because the selling
securityholders may offer all or some of their notes or the underlying common
stock from time to time, we cannot estimate the amount of the notes or
underlying common stock that will be held by the selling securityholders upon
the termination of any particular offering. The column showing ownership after
completion of the offering assumes that the selling securityholders will sell
all of the securities offered by this prospectus. The selling securityholders
listed in the table may have sold or transferred, in transactions exempt from
the registration requirements of the Securities Act, some or all of their notes
since the date on which the information in table is presented. Information about
the selling stockholders may change over time. Any change in this information
will be set forth in prospectus supplements, if required. None of the selling
securityholders or any of its affiliates, officers, directors or principal
equity holders has held any position or office or has had any material
relationship with us or our affiliates within the past three years.







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                                                                                            # OF SHARES OF COMMON
                                                                                                 STOCK TO BE
   NAME OF SELLING      PRINCIPAL AMOUNT                  # OF SHARES OF                     BENEFICIALLY OWNED
    SECURITYHOLDER          OF NOTES                       COMMON STOCK     # OF SHARES      AFTER COMPLETION OF
                          BENEFICIALLY      PERCENTAGE     BENEFICIALLY      OF COMMON        OFFERING AND % OF
                         OWNED THAT MAY      OF NOTES     OWNED PRIOR TO     STOCK THAT         COMMON STOCK
                           BE SOLD ($)     OUTSTANDING   THE OFFERING(1)   MAY BE SOLD(1)      OUTSTANDING(2)
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ABN AMRO Securities
LLC                       1,000,000           0.57%          14,238          14,238                  0
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Any other holder of
notes or future
transferee, pledgee
donee or successor(3)
(4)
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(1)  Assumes conversion of all of the holder's notes at a conversion price of
     $70.23 a share of common stock. Fractions of a share are not included for
     the purposes of this calculation. The conversion price will be subject to
     adjustment as described under "Description of Notes - Conversion of Notes."
     As a result, the amount of common stock issuable upon conversion of the
     notes may increase or decrease in the future.

(2)  Each selling stockholder listed herein will own less than 1% of the total
     shares of common stock outstanding upon completion of the offering.

(3)  Information about other selling securityholders will be set forth in
     prospectus supplements, if required.

(4)  Assumes that any other holders of notes, or any future transferees,
     pledgees, donees or successors of or from any other such holders of notes,
     do not beneficially own any common stock other than the common stock
     issuable upon conversion of the notes at the initial conversion rate.


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INVESTING IN THE SECURITIES OFFERED HEREBY INVOLVES A HIGH DEGREE OF RISK. SEE
"RISK FACTORS" BEGINNING ON PAGE 6 OF THE ACCOMPANYING PROSPECTUS.

THE SECURITIES AND EXCHANGE COMMISSION AND STATE SECURITIES REGULATORS HAVE NOT
APPROVED OR DISAPPROVED OF THESE SECURITIES OR DETERMINED IF THIS PROSPECTUS
SUPPLEMENT OR THE ACCOMPANYING PROSPECTUS IS TRUTHFUL OR COMPLETE. ANY
REPRESENTATION TO THE CONTRARY IS A CRIMINAL OFFENSE.

                              ---------------------

           The date of this Prospectus Supplement is October 24, 2001