<PAGE>
 
As filed with the Securities Exchange Commission on December 22, 1998
                                                      Registration No. 333-_____
================================================================================

                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549

                                    FORM S-8
                             REGISTRATION STATEMENT
                                     UNDER
                           THE SECURITIES ACT OF 1933

                               OSI SYSTEMS, INC.
             (Exact Name of Registrant as Specified in its Charter)

           California                                   33-0238801
(State or Other Jurisdiction of                       (I.R.S. Employer
Incorporation or Organization)                        Identification No.)
 
                             12525 Chadron Avenue,
                              Hawthorne, CA 90250
                    (Address of Principal Executive Offices)

                 OSI SYSTEMS, INC. EMPLOYEE STOCK PURCHASE PLAN
                            (Full Title of the Plan)

                                 Deepak Chopra
          Chairman of the Board, President and Chief Executive Officer
                               OSI Systems, Inc.
                              12525 Chadron Avenue
                              Hawthorne, CA 90250
                    (Name and Address of Agent for Service)
                                 (310) 978-0516
         (Telephone Number, Including Area Code, of Agent for Service)

                                   COPIES TO:
                            Gerald M. Chizever, Esq.
                             Lance Jon Kimmel, Esq.
                  Richman, Lawrence, Mann, Chizever & Phillips
                            9601 Wilshire Boulevard
                                   Penthouse
                            Beverly Hills, CA 90210
                                 (310) 274-8300

================================================================================

                        CALCULATION OF REGISTRATION FEE
                        ===============================
<TABLE>
<CAPTION>
                                              Proposed            Proposed
Title of                                       Maximum             Maximum
Securities to be        Amount to be       Offering Price         Aggregate            Amount of
registered(1)           Registered(1)       Per Share(2)      Offering Price(2)   Registration Fee(3)
-------------------   -----------------   -----------------   -----------------   -------------------
<S>                   <C>                 <C>                 <C>                 <C>
Common Stock,         200,000 shares               $7.00          $1,400,000               $389.20
 no par value
=====================================================================================================
</TABLE>

(1)  Pursuant to Rule 416(a), also covers additional securities that may be
     offered as a result of stock splits, stock dividends or similar
     transactions.

(2)  Estimated solely for purposes of determining the registration fee.

(3)  Calculated pursuant to Rule 457(a) and Rule 457(c), based upon the average
     of the high and low prices of the Common Stock on the Nasdaq National
     Market on December 16, 1998, which was $7.00.
<PAGE>
 
                                  INTRODUCTION

     This Registration Statement on Form S-8 is filed by OSI Systems, Inc., a
California corporation (the "Company" or the "Registrant"), relating to 200,000
shares of its Common Stock, no par value (the "Common Stock"), issuable to
eligible employees of the Company and its subsidiaries under the OSI Systems,
Inc. Employee Stock Purchase Plan (the "Plan").

                                     PART I

                INFORMATION REQUIRED IN SECTION 10(a) PROSPECTUS

     Item 1.   Plan Information.
               ---------------- 

     Not filed as part of this Registration Statement pursuant to Note to Part 1
of Form S-8.

     Item 2.   Registrant Information and Employee Plan Annual Information.
               ----------------------------------------------------------- 

     Not filed as part of this Registration Statement pursuant to Note to Part 1
of Form S-8.


                                       2
<PAGE>
 
                                    PART II

               INFORMATION REQUIRED IN THE REGISTRATION STATEMENT

      Item 3.   Incorporation of Documents by Reference.
                --------------------------------------- 

      The following documents, which previously have been filed by the Company
with the Securities and Exchange Commission (the "Commission"), are incorporated
herein by reference and made a part hereof:

(i)   The Company's latest Annual Report on Form 10-K for the fiscal year ended
      June 30, 1998;

(ii)  All other reports filed pursuant to Section 13(a) or 15(d) of the
      Securities Exchange Act of 1934 (the "Exchange Act") since the end of the
      fiscal year covered by the Annual Report referred to in (i) above; and

(iii) The description of the Company's Common Stock contained in the Company's
      Registration Statement on Form S-1 (Registration No. 333-29179), filed
      with the Commission on June 13, 1997, including any amendment or report
      filed for the purpose of updating such description.

      All reports and other documents filed by the Company pursuant to Sections
13(a), 13(c), 14 or 15(d) of the Exchange Act subsequent to the date of this
Registration Statement and prior to the filing of a post-effective amendment
hereto, which indicates that all securities offered hereunder have been sold or
which deregisters all securities then remaining unsold, shall be deemed to be
incorporated by reference herein and to be a part hereof from the date of filing
of such documents.

      For purposes of this Registration Statement, any document or any statement
contained in a document incorporated or deemed to be incorporated herein by
reference shall be deemed to be modified or superseded to the extent that a
subsequently filed document or a statement contained therein or in any other
subsequently filed document which also is or is deemed to be incorporated herein
by reference modifies or supersedes such document or such statement in such
document.  Any statement so modified or superseded shall not be deemed, except
as so modified or superseded, to constitute a part of this Registration
Statement.

      Item 4.   Description of Securities.
                ------------------------- 

      Not applicable.

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

      Not applicable.


                                     II-1
<PAGE>
 
     Item 6.   Indemnification of Directors and Officers.
               ----------------------------------------- 

     The Company's Articles of Incorporation (the "Articles") provide that,
pursuant to the California Corporations Code, the liability of the directors of
the Company for monetary damages shall be eliminated to the fullest extent
permissible under California law.  This is intended to eliminate the personal
liability of a director for monetary damages in an action brought by, or in the
right of, the Company for breach of a director's duties to the Company or its
shareholders.  This provision in the Articles does not eliminate the directors'
fiduciary duty and does not apply to certain liabilities:  (i) for acts or
omissions that involve intentional misconduct or a knowing and culpable
violation of law; (ii) for acts or omissions that a director believes to be
contrary to the best interest of the Company or its shareholders or that involve
the absence of good faith on the part of the director; (iii) for any transaction
from which a director derived an improper personal benefit; (iv) for acts or
omissions that show a reckless disregard for the director's duty to the Company
or its shareholders in circumstances in which the director was aware, or should
have been aware, in the ordinary course of performing a director's duties, of a
risk of serious injury to the Company or its shareholders; (v) for acts or
omissions that constitute an unexcused pattern of inattention that amounts to an
abdication of the director's duty to the Company or its shareholders; (vi) with
respect to certain transactions or the approval of transactions in which a
director has a material financial interest; and (vii) expressly imposed by
statute for approval of certain improper distributions to shareholders or
certain loans or guarantees.  This provision also does not limit or eliminate
the rights of the Company or any shareholder to seek non-monetary relief such as
an injunction or rescission in the event of a breach of a director's duty of
care.  The Company's Amended and Restated Bylaws require the Company to
indemnify its officers and directors under certain circumstances.  Among other
things, the Bylaws require the Company to indemnify directors and officers
against certain liabilities that may arise by reason of their status or service
as directors and officers and allows the Company to advance their expenses
incurred as a result of any proceeding against them as to which they could be
indemnified.

     Section 317 of the California Corporations Code ("Section 317") provides
that a California corporation may indemnify any person who was or is a party or
is threatened to be made a party to any threatened, pending or completed action
or proceeding, whether civil, criminal, administrative or investigative (other
than action by or in the right of the corporation) by reason of the fact that he
is or was a director, officer, employee or agent of the corporation or is or was
serving at the request of the corporation as a director, officer, employee or
agent of another corporation or enterprise, against expenses, judgments, fines
and amounts paid in settlement actually and reasonably incurred by him in
connection with such action or proceeding if he acted in good faith and in a
manner he reasonably believed to be in or not opposed to the best interest of
the corporation, and, with respect to any criminal action or proceeding, had no
cause to believe his conduct was unlawful.

     Section 317 also provides that a California corporation may indemnify any
person who was or is a party or is threatened to be made a party to any
threatened, pending or completed action or suit by or in the right of the
corporation to procure a judgment in its


                                     II-2
<PAGE>
 
favor by reason of the fact that such person acted in any of the capacities set
forth above, against expenses actually and reasonably incurred by him in
connection with the defense or settlement of such action or suit if he acted
under similar standards, except that no indemnification may be made in respect
to any claim, issue or matter as to which such persons shall have been adjudged
to be liable to the corporation unless and only to the extent that the court in
which such action or suit was brought shall determine that despite the
adjudication of liability, such person is fairly and reasonably entitled to be
indemnified for such expenses which the court shall deem proper.

     Section 317 provides further that to the extent a director or officer of a
California corporation has been successful in the defense of any action, suit or
proceeding referred to in the previous paragraphs or in the defense of any
claim, issue or matter therein, he shall be indemnified against expenses
actually and reasonably incurred by him in connection therewith; that
indemnification authorized by Section 317 shall not be deemed exclusive of any
other rights to which the indemnified party may be entitled; and that the
corporation may purchase and maintain insurance on behalf of a director or
officer of the corporation against any liability asserted against him or
incurred by him in any such capacity or arising out of his status as such
whether or not the corporation would have the power to indemnify him against
such liabilities under Section 317.

     In May 1994, the Company entered into indemnification agreements with
Deepak Chopra, Ajay Mehra and Thomas K. Hickman in connection with certain
personal guarantees provided by them to a Singapore financial institution that
provided a loan to OSI Singapore, a subsidiary of the Company.  The
indemnification agreements provide that the Company shall indemnify Messrs.
Chopra, Mehra and Hickman against all debts, liabilities, damages, claims,
expenses and costs including attorneys' fees incurred by them in connection with
OSI Singapore's inability to fulfill its obligations under the loan and their
respective guarantees of such loan.  Messrs. Chopra, Mehra and Hickman are
directors and/or executive officers of the Company.

     In connection with certain settlements entered into pursuant to consent
agreements, the Company's subsidiary, UDT Sensors, agreed to pay the United
States government a total of $1,500,000 in five annual installments ending on
March 31, 1999.  In order to ensure the full payment, Deepak Chopra personally
guaranteed the payment of $750,000 of the foregoing amount.  The Company entered
into an indemnification agreement with Mr. Chopra pursuant to which the Company
shall indemnify Mr. Chopra against all debts, liabilities, damages, claims,
expenses and costs including attorneys' fees incurred by him in connection with
his guarantee of the payment of $750,000.

     In addition, the Company entered into indemnity agreements ("Indemnity
Agreement(s)") with each of its directors and executive officers prior to the
consummation of the offering of the Company's Common Stock covered by its
Registration Statement on Form S-1 (Registration No. 333-29179), filed with the
Commission on June 13, 1997, as subsequently amended (the "S-1 Registration
Statement").  Each such Indemnity Agreement (the form of which is incorporated
by reference to Exhibit 10.10 to Amendment No. 2 to the S-1 Registration
Statement, filed with the Commission on August 15, 1997) provides


                                     II-3
<PAGE>
 
that the Company shall indemnify the indemnitee against expenses, including
reasonable attorneys' fees, judgements, penalties, fines and amounts paid in
settlement actually and reasonably incurred by him in connection with any civil
or criminal action or administrative proceeding arising out of the performance
of his duties as a director or officer.  Such indemnification is available if
the indemnitee acted in good faith and in a manner he reasonably believed to be
in or not opposed to the best interests of the Company, and, with respect to any
criminal action, had no reasonable cause to believe his conduct was unlawful.
Each Indemnity Agreement permits the director or officer that is party thereto
to bring suit to seek recovery of amounts due under the Indemnity Agreement and
to recover the expenses of such a suit if he is successful.

     The Underwriting Agreement filed as Exhibit 1.1 to the S-1 Registration
Statement provides for indemnification by the underwriters of the Company and
its officers and directors for certain liabilities arising under the Securities
Act of 1933, as amended (the "Securities Act"), or otherwise.

     The Company has been advised that it is the position of the Commission that
insofar as the foregoing provisions may be invoked to disclaim liability for
damages arising under the Securities Act, the provision is against public policy
as expressed in the Securities Act and is therefore unenforceable.  Such
limitation of liability also does not affect the availability of equitable
remedies such as injunctive relief or rescission.

     Item 7.   Exemption from Registration Claimed.
               ----------------------------------- 

     Not applicable.

     Item 8.   Exhibits.
               -------- 

     Unless otherwise indicated below as being incorporated by reference to
another filing of the Company with the Commission, each of the following
exhibits is filed herewith:

<TABLE>
<CAPTION>
Exhibit
Number                Exhibit Description
-------               -------------------
<C>       <S>
    4.1   OSI Systems, Inc. Employee Stock Purchase Plan.
    5.1   Legal Opinion of Richman, Lawrence, Mann, Chizever & Phillips.
   23.1   Consent of Richman, Lawrence, Mann, Chizever & Phillips (contained in
          Exhibit 5.1).
   23.2   Consent of Deloitte & Touche LLP (independent auditors).
     24   Power of Attorney (contained on signature page hereto).
</TABLE>

Item 9.      Undertakings.
             -------------

     (a) The undersigned Registrant hereby undertakes:


                                     II-4
<PAGE>
 
          (1) To file, during any period in which offers or sales are being
made, a post-effective amendment to this registration statement:

               (i) To include any prospectus required by section 10(a)(3) of the
Securities Act;

               (ii) To reflect in the prospectus any facts or events arising
after the effective date of the registration statement (or the most recent post-
effective amendment thereof) which, individually or in the aggregate, represent
a fundamental change in the information set forth in the registration statement.
Notwithstanding the foregoing, any increase or decrease in volume of securities
offered (if the total dollar value of securities offered would not exceed that
which was registered) and any deviation from the low or high and of the
estimated maximum offering range may be reflected in the form of prospectus
filed with the Commission pursuant to Rule 424(b) if, in the aggregate, the
changes in volume and price represent no more than a 20 percent change in the
maximum aggregate offering price set forth in the "Calculation of Registration
Fee" table in the effective registration statement;

               (iii) To include any material information with respect to the
plan of distribution not previously disclosed in the registration statement or
any material change to such information in the registration statement;

provided, however, that paragraphs (a)(1)(i) and (a)(1)(ii) do not apply if the
information required to be included in a post-effective amendment by those
paragraphs is contained in periodic reports filed by the Registrant pursuant to
Section 13 or Section 15(d) of the Exchange Act that are incorporated by
reference in this registration statement.

          (2) That, for the purpose of determining any liability under the
Securities Act, each such post-effective amendment shall be deemed to be a new
registration statement relating to the securities offered therein, and the
offering of such securities at that time shall be deemed to be the initial bona
fide offering thereof.

          (3) To remove from registration by means of a post-effective amendment
any of the securities being registered which remain unsold at the termination of
the offering.

     (b) The undersigned Registrant hereby undertakes that, for purposes of
determining any liability under the Securities Act, each filing of the
Registrant's annual report pursuant to Section 13(a) or Section 15(d) of the
Exchange Act (and, where applicable, each filing of an employee benefit plan's
annual report pursuant to Section 15(d) of the Securities Exchange Act) that is
incorporated by reference in the Registration Statement shall be deemed to be a
new registration statement relating to the securities offered therein, and the
offering of such securities at that time shall be deemed to be the initial bona
fide offering thereof.

     (c) Insofar as indemnification for liabilities arising under the Securities
Act may be permitted to directors, officers and controlling persons of the
Registrant pursuant to the foregoing provisions, or otherwise, the Registrant
has been advised that in the opinion of the Securities and Exchange Commission
such indemnification is against public policy as expressed in the Securities Act
and is, therefore, unenforceable. In the event that a claim for indemnification
against such liabilities (other than the payment by the Registrant of expenses
incurred or paid by a director, officer or controlling person of the Registrant
in the successful defense of any action, suit or proceeding) is asserted by such
director, officer or controlling person in connection with the securities being
registered, the Registrant will, unless in the opinion of its counsel the matter
has been settled by controlling precedent, submit to a court of appropriate
jurisdiction the question whether such indemnification by it is against public
policy as expressed in the Securities Act and will be governed by the final
adjudication of such issue.


                                     II-5
<PAGE>
 
                                   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 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 Hawthorne, State of California, this 17th day of
December, 1998.

                                      OSI SYSTEMS, INC.



                                      By: /s/ Deepak Chopra
                                         ---------------------------------------
                                          Deepak Chopra, Chairman of the Board, 
                                          President and Chief Executive Officer

     Each person whose signature appears below constitutes and appoints Deepak
Chopra and Ajay Mehra, and each of them, his true and lawful attorneys-in-fact
and agents, each with full power of substitution and resubstitution, severally,
for him and in his name, place and stead, in any and all capacities, to sign any
and all amendments (including post-effective amendments) to this Registration
Statement, and to file the same, with all exhibits thereto and other documents
in connection therewith, with the Securities and Exchange Commission, granting
unto said attorneys-in-fact and agents, and each of them, full power and
authority to do and perform each and every act and thing requisite and necessary
to be done in and about the premises, as fully to all intents and purposes as he
might or could do in person, hereby ratifying and confirming all that said
attorneys-in-fact and agents, or any of them or their or his substitute or
substitutes, may lawfully do or cause to be done by virtue hereof.

     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.

<TABLE>
<CAPTION>
Signature                         Title                       Date
-----------------   ---------------------------------   -----------------
<S>                 <C>                                 <C>

/s/ Deepak Chopra   Chairman of the Board,              December 17, 1998
------------------  President and Chief Executive
Deepak Chopra       Officer (Principal Executive
                    Officer)
                  
/s/ Ajay Mehra      Vice President, Chief Financial     December 17, 1998
------------------  Officer (Principal Financial and
Ajay Mehra          Accounting Officer), Secretary
                    and Director
                  
                  
/s/ Steven C. Good  Director                            December 17, 1998
------------------
Steven C. Good    
                  
/s/ Meyer Luskin    Director                            December 17, 1998
------------------
Meyer Luskin      
                  
/s/ Madan G. Syal   Director                            December 17, 1998
------------------
Madan G. Syal     
</TABLE> 

                                     II-6
<PAGE>
 
                                 EXHIBIT INDEX

<TABLE>
<CAPTION>
Exhibit
Number                         Exhibit Description
-------   ---------------------------------------------------------------------
<C>       <S>
    4.1   OSI Systems, Inc. Employee Stock Purchase Plan.
    5.1   Legal opinion of Richman, Lawrence, Mann, Chizever & Phillips.
   23.1   Consent of Richman, Lawrence, Mann, Chizever & Phillips (contained in
          Exhibit 5.1).
   23.2   Consent of Deloitte & Touche LLP (independent auditors).
     24   Power of Attorney (contained on signature page hereto).
</TABLE>
[{"type": "S-8", "sequence": "1", "description": "FORM S-8", "secsgml_size_bytes": 24755}]
{"company-data": {"conformed-name": "OSI SYSTEMS INC", "cik": "0001039065", "assigned-sic": "3674", "irs-number": "330238801", "state-of-incorporation": "CA", "fiscal-year-end": "0630"}, "filing-values": {"form-type": "S-8", "act": "33", "file-number": "333-69433", "film-number": "98773688"}, "business-address": {"street1": "12525 CHADRON AVE", "city": "HAWTHORNE", "state": "CA", "zip": "90250", "phone": "3109780516"}, "mail-address": {"street1": "12525 CHADRON AVENUE", "city": "HAWTHORNE", "state": "CA", "zip": "90250"}}
As filed with the Securities Exchange Commission on December 22, 1998
                                                      Registration No. 333-_____
================================================================================

                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549

                                    FORM S-8
                             REGISTRATION STATEMENT
                                     UNDER
                           THE SECURITIES ACT OF 1933

                               OSI SYSTEMS, INC.
             (Exact Name of Registrant as Specified in its Charter)

           California                                   33-0238801
(State or Other Jurisdiction of                       (I.R.S. Employer
Incorporation or Organization)                        Identification No.)
 
                             12525 Chadron Avenue,
                              Hawthorne, CA 90250
                    (Address of Principal Executive Offices)

                 OSI SYSTEMS, INC. EMPLOYEE STOCK PURCHASE PLAN
                            (Full Title of the Plan)

                                 Deepak Chopra
          Chairman of the Board, President and Chief Executive Officer
                               OSI Systems, Inc.
                              12525 Chadron Avenue
                              Hawthorne, CA 90250
                    (Name and Address of Agent for Service)
                                 (310) 978-0516
         (Telephone Number, Including Area Code, of Agent for Service)

                                   COPIES TO:
                            Gerald M. Chizever, Esq.
                             Lance Jon Kimmel, Esq.
                  Richman, Lawrence, Mann, Chizever & Phillips
                            9601 Wilshire Boulevard
                                   Penthouse
                            Beverly Hills, CA 90210
                                 (310) 274-8300

================================================================================

                        CALCULATION OF REGISTRATION FEE
                        ===============================
Proposed            Proposed
Title of                                       Maximum             Maximum
Securities to be        Amount to be       Offering Price         Aggregate            Amount of
registered(1)           Registered(1)       Per Share(2)      Offering Price(2)   Registration Fee(3)
-------------------   -----------------   -----------------   -----------------   -------------------
Common Stock,         200,000 shares               $7.00          $1,400,000               $389.20
 no par value
=====================================================================================================
(1)  Pursuant to Rule 416(a), also covers additional securities that may be
     offered as a result of stock splits, stock dividends or similar
     transactions.

(2)  Estimated solely for purposes of determining the registration fee.

(3)  Calculated pursuant to Rule 457(a) and Rule 457(c), based upon the average
     of the high and low prices of the Common Stock on the Nasdaq National
     Market on December 16, 1998, which was $7.00.
INTRODUCTION

     This Registration Statement on Form S-8 is filed by OSI Systems, Inc., a
California corporation (the "Company" or the "Registrant"), relating to 200,000
shares of its Common Stock, no par value (the "Common Stock"), issuable to
eligible employees of the Company and its subsidiaries under the OSI Systems,
Inc. Employee Stock Purchase Plan (the "Plan").

                                     PART I

                INFORMATION REQUIRED IN SECTION 10(a) PROSPECTUS

     Item 1.   Plan Information.
               ---------------- 

     Not filed as part of this Registration Statement pursuant to Note to Part 1
of Form S-8.

     Item 2.   Registrant Information and Employee Plan Annual Information.
               ----------------------------------------------------------- 

     Not filed as part of this Registration Statement pursuant to Note to Part 1
of Form S-8.

                                       2
PART II

               INFORMATION REQUIRED IN THE REGISTRATION STATEMENT

      Item 3.   Incorporation of Documents by Reference.
                --------------------------------------- 

      The following documents, which previously have been filed by the Company
with the Securities and Exchange Commission (the "Commission"), are incorporated
herein by reference and made a part hereof:

(i)   The Company's latest Annual Report on Form 10-K for the fiscal year ended
      June 30, 1998;

(ii)  All other reports filed pursuant to Section 13(a) or 15(d) of the
      Securities Exchange Act of 1934 (the "Exchange Act") since the end of the
      fiscal year covered by the Annual Report referred to in (i) above; and

(iii) The description of the Company's Common Stock contained in the Company's
      Registration Statement on Form S-1 (Registration No. 333-29179), filed
      with the Commission on June 13, 1997, including any amendment or report
      filed for the purpose of updating such description.

      All reports and other documents filed by the Company pursuant to Sections
13(a), 13(c), 14 or 15(d) of the Exchange Act subsequent to the date of this
Registration Statement and prior to the filing of a post-effective amendment
hereto, which indicates that all securities offered hereunder have been sold or
which deregisters all securities then remaining unsold, shall be deemed to be
incorporated by reference herein and to be a part hereof from the date of filing
of such documents.

      For purposes of this Registration Statement, any document or any statement
contained in a document incorporated or deemed to be incorporated herein by
reference shall be deemed to be modified or superseded to the extent that a
subsequently filed document or a statement contained therein or in any other
subsequently filed document which also is or is deemed to be incorporated herein
by reference modifies or supersedes such document or such statement in such
document.  Any statement so modified or superseded shall not be deemed, except
as so modified or superseded, to constitute a part of this Registration
Statement.

      Item 4.   Description of Securities.
                ------------------------- 

      Not applicable.

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

      Not applicable.

                                     II-1
Item 6.   Indemnification of Directors and Officers.
               ----------------------------------------- 

     The Company's Articles of Incorporation (the "Articles") provide that,
pursuant to the California Corporations Code, the liability of the directors of
the Company for monetary damages shall be eliminated to the fullest extent
permissible under California law.  This is intended to eliminate the personal
liability of a director for monetary damages in an action brought by, or in the
right of, the Company for breach of a director's duties to the Company or its
shareholders.  This provision in the Articles does not eliminate the directors'
fiduciary duty and does not apply to certain liabilities:  (i) for acts or
omissions that involve intentional misconduct or a knowing and culpable
violation of law; (ii) for acts or omissions that a director believes to be
contrary to the best interest of the Company or its shareholders or that involve
the absence of good faith on the part of the director; (iii) for any transaction
from which a director derived an improper personal benefit; (iv) for acts or
omissions that show a reckless disregard for the director's duty to the Company
or its shareholders in circumstances in which the director was aware, or should
have been aware, in the ordinary course of performing a director's duties, of a
risk of serious injury to the Company or its shareholders; (v) for acts or
omissions that constitute an unexcused pattern of inattention that amounts to an
abdication of the director's duty to the Company or its shareholders; (vi) with
respect to certain transactions or the approval of transactions in which a
director has a material financial interest; and (vii) expressly imposed by
statute for approval of certain improper distributions to shareholders or
certain loans or guarantees.  This provision also does not limit or eliminate
the rights of the Company or any shareholder to seek non-monetary relief such as
an injunction or rescission in the event of a breach of a director's duty of
care.  The Company's Amended and Restated Bylaws require the Company to
indemnify its officers and directors under certain circumstances.  Among other
things, the Bylaws require the Company to indemnify directors and officers
against certain liabilities that may arise by reason of their status or service
as directors and officers and allows the Company to advance their expenses
incurred as a result of any proceeding against them as to which they could be
indemnified.

     Section 317 of the California Corporations Code ("Section 317") provides
that a California corporation may indemnify any person who was or is a party or
is threatened to be made a party to any threatened, pending or completed action
or proceeding, whether civil, criminal, administrative or investigative (other
than action by or in the right of the corporation) by reason of the fact that he
is or was a director, officer, employee or agent of the corporation or is or was
serving at the request of the corporation as a director, officer, employee or
agent of another corporation or enterprise, against expenses, judgments, fines
and amounts paid in settlement actually and reasonably incurred by him in
connection with such action or proceeding if he acted in good faith and in a
manner he reasonably believed to be in or not opposed to the best interest of
the corporation, and, with respect to any criminal action or proceeding, had no
cause to believe his conduct was unlawful.

     Section 317 also provides that a California corporation may indemnify any
person who was or is a party or is threatened to be made a party to any
threatened, pending or completed action or suit by or in the right of the
corporation to procure a judgment in its

                                     II-2
favor by reason of the fact that such person acted in any of the capacities set
forth above, against expenses actually and reasonably incurred by him in
connection with the defense or settlement of such action or suit if he acted
under similar standards, except that no indemnification may be made in respect
to any claim, issue or matter as to which such persons shall have been adjudged
to be liable to the corporation unless and only to the extent that the court in
which such action or suit was brought shall determine that despite the
adjudication of liability, such person is fairly and reasonably entitled to be
indemnified for such expenses which the court shall deem proper.

     Section 317 provides further that to the extent a director or officer of a
California corporation has been successful in the defense of any action, suit or
proceeding referred to in the previous paragraphs or in the defense of any
claim, issue or matter therein, he shall be indemnified against expenses
actually and reasonably incurred by him in connection therewith; that
indemnification authorized by Section 317 shall not be deemed exclusive of any
other rights to which the indemnified party may be entitled; and that the
corporation may purchase and maintain insurance on behalf of a director or
officer of the corporation against any liability asserted against him or
incurred by him in any such capacity or arising out of his status as such
whether or not the corporation would have the power to indemnify him against
such liabilities under Section 317.

     In May 1994, the Company entered into indemnification agreements with
Deepak Chopra, Ajay Mehra and Thomas K. Hickman in connection with certain
personal guarantees provided by them to a Singapore financial institution that
provided a loan to OSI Singapore, a subsidiary of the Company.  The
indemnification agreements provide that the Company shall indemnify Messrs.
Chopra, Mehra and Hickman against all debts, liabilities, damages, claims,
expenses and costs including attorneys' fees incurred by them in connection with
OSI Singapore's inability to fulfill its obligations under the loan and their
respective guarantees of such loan.  Messrs. Chopra, Mehra and Hickman are
directors and/or executive officers of the Company.

     In connection with certain settlements entered into pursuant to consent
agreements, the Company's subsidiary, UDT Sensors, agreed to pay the United
States government a total of $1,500,000 in five annual installments ending on
March 31, 1999.  In order to ensure the full payment, Deepak Chopra personally
guaranteed the payment of $750,000 of the foregoing amount.  The Company entered
into an indemnification agreement with Mr. Chopra pursuant to which the Company
shall indemnify Mr. Chopra against all debts, liabilities, damages, claims,
expenses and costs including attorneys' fees incurred by him in connection with
his guarantee of the payment of $750,000.

     In addition, the Company entered into indemnity agreements ("Indemnity
Agreement(s)") with each of its directors and executive officers prior to the
consummation of the offering of the Company's Common Stock covered by its
Registration Statement on Form S-1 (Registration No. 333-29179), filed with the
Commission on June 13, 1997, as subsequently amended (the "S-1 Registration
Statement").  Each such Indemnity Agreement (the form of which is incorporated
by reference to Exhibit 10.10 to Amendment No. 2 to the S-1 Registration
Statement, filed with the Commission on August 15, 1997) provides

                                     II-3
that the Company shall indemnify the indemnitee against expenses, including
reasonable attorneys' fees, judgements, penalties, fines and amounts paid in
settlement actually and reasonably incurred by him in connection with any civil
or criminal action or administrative proceeding arising out of the performance
of his duties as a director or officer.  Such indemnification is available if
the indemnitee acted in good faith and in a manner he reasonably believed to be
in or not opposed to the best interests of the Company, and, with respect to any
criminal action, had no reasonable cause to believe his conduct was unlawful.
Each Indemnity Agreement permits the director or officer that is party thereto
to bring suit to seek recovery of amounts due under the Indemnity Agreement and
to recover the expenses of such a suit if he is successful.

     The Underwriting Agreement filed as Exhibit 1.1 to the S-1 Registration
Statement provides for indemnification by the underwriters of the Company and
its officers and directors for certain liabilities arising under the Securities
Act of 1933, as amended (the "Securities Act"), or otherwise.

     The Company has been advised that it is the position of the Commission that
insofar as the foregoing provisions may be invoked to disclaim liability for
damages arising under the Securities Act, the provision is against public policy
as expressed in the Securities Act and is therefore unenforceable.  Such
limitation of liability also does not affect the availability of equitable
remedies such as injunctive relief or rescission.

     Item 7.   Exemption from Registration Claimed.
               ----------------------------------- 

     Not applicable.

     Item 8.   Exhibits.
               -------- 

     Unless otherwise indicated below as being incorporated by reference to
another filing of the Company with the Commission, each of the following
exhibits is filed herewith:
Exhibit
Number                Exhibit Description
-------               -------------------
4.1   OSI Systems, Inc. Employee Stock Purchase Plan.
    5.1   Legal Opinion of Richman, Lawrence, Mann, Chizever & Phillips.
   23.1   Consent of Richman, Lawrence, Mann, Chizever & Phillips (contained in
          Exhibit 5.1).
   23.2   Consent of Deloitte & Touche LLP (independent auditors).
     24   Power of Attorney (contained on signature page hereto).
Item 9.      Undertakings.
             -------------

     (a) The undersigned Registrant hereby undertakes:

                                     II-4
(1) To file, during any period in which offers or sales are being
made, a post-effective amendment to this registration statement:

               (i) To include any prospectus required by section 10(a)(3) of the
Securities Act;

               (ii) To reflect in the prospectus any facts or events arising
after the effective date of the registration statement (or the most recent post-
effective amendment thereof) which, individually or in the aggregate, represent
a fundamental change in the information set forth in the registration statement.
Notwithstanding the foregoing, any increase or decrease in volume of securities
offered (if the total dollar value of securities offered would not exceed that
which was registered) and any deviation from the low or high and of the
estimated maximum offering range may be reflected in the form of prospectus
filed with the Commission pursuant to Rule 424(b) if, in the aggregate, the
changes in volume and price represent no more than a 20 percent change in the
maximum aggregate offering price set forth in the "Calculation of Registration
Fee" table in the effective registration statement;

               (iii) To include any material information with respect to the
plan of distribution not previously disclosed in the registration statement or
any material change to such information in the registration statement;

provided, however, that paragraphs (a)(1)(i) and (a)(1)(ii) do not apply if the
information required to be included in a post-effective amendment by those
paragraphs is contained in periodic reports filed by the Registrant pursuant to
Section 13 or Section 15(d) of the Exchange Act that are incorporated by
reference in this registration statement.

          (2) That, for the purpose of determining any liability under the
Securities Act, each such post-effective amendment shall be deemed to be a new
registration statement relating to the securities offered therein, and the
offering of such securities at that time shall be deemed to be the initial bona
fide offering thereof.

          (3) To remove from registration by means of a post-effective amendment
any of the securities being registered which remain unsold at the termination of
the offering.

     (b) The undersigned Registrant hereby undertakes that, for purposes of
determining any liability under the Securities Act, each filing of the
Registrant's annual report pursuant to Section 13(a) or Section 15(d) of the
Exchange Act (and, where applicable, each filing of an employee benefit plan's
annual report pursuant to Section 15(d) of the Securities Exchange Act) that is
incorporated by reference in the Registration Statement shall be deemed to be a
new registration statement relating to the securities offered therein, and the
offering of such securities at that time shall be deemed to be the initial bona
fide offering thereof.

     (c) Insofar as indemnification for liabilities arising under the Securities
Act may be permitted to directors, officers and controlling persons of the
Registrant pursuant to the foregoing provisions, or otherwise, the Registrant
has been advised that in the opinion of the Securities and Exchange Commission
such indemnification is against public policy as expressed in the Securities Act
and is, therefore, unenforceable. In the event that a claim for indemnification
against such liabilities (other than the payment by the Registrant of expenses
incurred or paid by a director, officer or controlling person of the Registrant
in the successful defense of any action, suit or proceeding) is asserted by such
director, officer or controlling person in connection with the securities being
registered, the Registrant will, unless in the opinion of its counsel the matter
has been settled by controlling precedent, submit to a court of appropriate
jurisdiction the question whether such indemnification by it is against public
policy as expressed in the Securities Act and will be governed by the final
adjudication of such issue.

                                     II-5
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 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 Hawthorne, State of California, this 17th day of
December, 1998.

                                      OSI SYSTEMS, INC.

                                      By: /s/ Deepak Chopra
                                         ---------------------------------------
                                          Deepak Chopra, Chairman of the Board, 
                                          President and Chief Executive Officer

     Each person whose signature appears below constitutes and appoints Deepak
Chopra and Ajay Mehra, and each of them, his true and lawful attorneys-in-fact
and agents, each with full power of substitution and resubstitution, severally,
for him and in his name, place and stead, in any and all capacities, to sign any
and all amendments (including post-effective amendments) to this Registration
Statement, and to file the same, with all exhibits thereto and other documents
in connection therewith, with the Securities and Exchange Commission, granting
unto said attorneys-in-fact and agents, and each of them, full power and
authority to do and perform each and every act and thing requisite and necessary
to be done in and about the premises, as fully to all intents and purposes as he
might or could do in person, hereby ratifying and confirming all that said
attorneys-in-fact and agents, or any of them or their or his substitute or
substitutes, may lawfully do or cause to be done by virtue hereof.

     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/ Deepak Chopra   Chairman of the Board,              December 17, 1998
------------------  President and Chief Executive
Deepak Chopra       Officer (Principal Executive
                    Officer)
                  
/s/ Ajay Mehra      Vice President, Chief Financial     December 17, 1998
------------------  Officer (Principal Financial and
Ajay Mehra          Accounting Officer), Secretary
                    and Director
                  
                  
/s/ Steven C. Good  Director                            December 17, 1998
------------------
Steven C. Good    
                  
/s/ Meyer Luskin    Director                            December 17, 1998
------------------
Meyer Luskin      
                  
/s/ Madan G. Syal   Director                            December 17, 1998
------------------
Madan G. Syal
II-6
EXHIBIT INDEX
Exhibit
Number                         Exhibit Description
-------   ---------------------------------------------------------------------
4.1   OSI Systems, Inc. Employee Stock Purchase Plan.
    5.1   Legal opinion of Richman, Lawrence, Mann, Chizever & Phillips.
   23.1   Consent of Richman, Lawrence, Mann, Chizever & Phillips (contained in
          Exhibit 5.1).
   23.2   Consent of Deloitte & Touche LLP (independent auditors).
     24   Power of Attorney (contained on signature page hereto).