101




                                  EXHIBIT 10.4
                                  ------------



           This is an Exhibit to the Form 20-F of Sinovac Biotech Ltd.
           -----------------------------------------------------------


                     Attached find the following materials:


     Consulting Agreement entered into between the Company and Michael Tan,
     ----------------------------------------------------------------------
                             dated November 1, 2003
                             ----------------------


                               End of Exhibit 10.4

                                   -----------



<PAGE>


                                       102




                              SINOVAC BIOTECH LTD.
                              --------------------
                        Suite #10-Epicurean, Woods Centre
                                 P.O. Box W-645
                        St. John's, Antigua, West Indies


November 1, 2003

VIA FAX    65-6732-0086
-----------------------

Michael Tan
-----------
4 Keng Chin Rd. #02-01
Singapore 258707

Attention:  Mr. Michael Tan

Dear Sirs:

Re:  Consulting Agreement with Sinovac Biotech Ltd. (the "Company")
-------------------------------------------------------------------

This  correspondence  will specify the consulting  arrangement  (the "Consulting
Agreement") between the Company and Michael Tan.

The terms and conditions of the Consulting Agreement are as follows:

1.   Services.  During  the Term (as  hereinafter  defined)  of this  Consulting
     --------
     Agreement,  Michael  Tan (the  "Consultant")  shall  provide to the Company
     consulting  services  designed  to assist  the  Company in  management  and
     marketing to develop the business of the Company.

2.   Term. The term of this Consulting  Agreement (the "Term) is for a period of
     ----
     two years commencing on July 1, 2003 (the "Effective Date").

3.   Payment for Services. It is hereby agreed that the Consultant shall provide
     --------------------
     the consulting services for a monthly fee of US$8,000 (the "Fee") with such
     Fee being due and  payable by the  Company to the  Consultant  on the first
     business day of the month in advance.  In  addition,  it is agreed that the
     Consultant shall be reimbursed for all expenses  incurred by the Consultant
     for the benefit of the Company  (collectively,  the  "Expenses")  and which
     Expenses  shall be payable by the Company within 30 days of delivery by the
     Consultant of written  substantiation  on account of each such reimbursable
     Expense.




<PAGE>


                                       103




4.   Confidentiality  by the  Consultant.  The  Consultant  will not,  except as
     -----------------------------------
     authorized  or required by the  Consultant's  duties  hereunder,  reveal or
     divulge  to  any  person  or  companies  any  information   concerning  the
     organization,  business,  finances,  transactions  or other  affairs of the
     Company, or of any of its subsidiaries,  which may come to the Consultant's
     knowledge  during the Term and during the  continuance  of this  Consulting
     Agreement,   and  the  Consultant   will  keep  in  complete   secrecy  all
     confidential  information  entrusted to the  Consultant and will not use or
     attempt to use any such information in any manner which may injure or cause
     loss either directly or indirectly to the Company's respective  businesses.
     This  restriction  will  continue  to apply after the  termination  of this
     Consulting Agreement without limit in point of time but will cease to apply
     to information or knowledge which may come into the public domain.

5.   Indemnification.  The Company agrees to indemnify and hold  Consultant (the
     ---------------
     "Indemnified  Person") harmless from and against losses,  claims,  damages,
     liabilities,   costs,  or  expenses  including  reasonable  attorney's  and
     accountant's  fees joint and several arising out of the performance of this
     Consulting Agreement, whether or not Consultant is a party to such dispute.
     The Company agrees that it shall also reimburse the Indemnified  Person for
     any attorney's and costs incurred in enforcing this Indemnification against
     the Company.

6.   No Indemnification.  This indemnity shall not apply, however, where a court
     ------------------
     of  competent   jurisdiction  has  made  a  final  determination  that  the
     Consultant  engaged in gross  recklessness  and willful  misconduct  in the
     performance  of its  services  hereunder  which  gave rise to loss,  claim,
     damage,  liability, cost or exposure sought to be recovered hereunder. (But
     pending any such final determination, the indemnification and reimbursement
     provision of this  Consulting  Agreement  shall apply and the Company shall
     perform  its  obligations   hereunder  to  reimburse   Consultant  for  its
     attorney's fees and expenses).

7.   Entire  Agreement.   This  Consulting   Agreement  sets  forth  the  entire
     -----------------
     understanding  of the parties  relating to the subject matter  hereof,  and
     supersedes  and  cancels  any  prior  communications,  understandings,  and
     agreements  between  the  parties.  This  Consulting  Agreement  cannot  be
     modified  or changed,  nor can any of its  provision  be waived,  except by
     written agreement signed by all parties.



<PAGE>


                                       104




If the Consultant is in accord with the forgoing,  please execute a copy of this
letter and the same will be binding on the parties.


Yours truly,
SINOVAC BIOTECH LTD.
--------------------
Per:


/s/ Lily Wang
----------------------------
LILY WANG, Director



The forgoing is hereby agreed to this 1st day of November,  2003 and Michael Tan
--------------------------------------------------------------------------------
declares himself bound to the terms.
------------------------------------


/s/ Michael Tan
----------------------------
Michael Tan, Consultant