6-K

FORM 6-K

SECURITIES AND EXCHANGE COMMISSION

Washington D.C. 20549

REPORT OF FOREIGN ISSUER

PURSUANT TO RULE 13a-16 OR 15d-16 OF THE

SECURITIES EXCHANGE ACT OF 1934

For the month of April, 2009

__________

Commission File Number: 001-32371

__________

SINOVAC BIOTECH LTD.

39 Shangdi Xi Road

Haidian District

Beijing 100085, People’s Republic of China

(Address of principal executive offices)

Indicate by check mark whether the registrant files or will file annual reports under cover Form 20-F or Form 40-F.

Form 20-F X              Form 40-F  _______

Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(1):________________

Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(7):________________

Indicate by check mark whether by furnishing the information contained in this Form, the registrant is also thereby furnishing the information to the Commission pursuant to Rule 12g3-2(b) under the Securities Exchange Act of 1934.

Yes  ______        No X     

If "Yes" is marked, indicate below the file number assigned to the registrant in connection with Rule 12g3-2(b):

82- N/A     

SINOVAC BIOTECH LTD.

Form 6-K

TABLE OF CONTENTS

	Page
Signature	3
Exhibit 99.1 – Press Release	4

SIGNATURE

           Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.

	SINOVAC BIOTECH LTD.
	By:	/s/ Weidong Yin
		Name:   Weidong Yin
		Title:      Chief Executive Officer, President
Date:  March 31, 2009

EX-99.1

Exhibit 99.1

Sinovac to Host Conference Call to Report Fourth Quarter and Full Year 2008 Financial Results

Wednesday April 1, 2009, 8:00 am EDT

BEIJING, April 1 /PRNewswire-Asia/ -- Sinovac Biotech Ltd. (Amex: SVA - News), a leading provider of vaccines in China, today announced that it will host a conference call on Thursday, April 9, 2009 at 9:00 a.m. ET (9 p.m. China Standard Time) to review the Company's financial results for the fourth quarter and full year ended December 31, 2008, and to provide an update on recent corporate developments.

To access the conference call, please dial 1-877-407-4018 (USA) or 1-201-689-8471 (international). A replay of the call will be available from 12:00 p.m. ET on April 9, 2009 until 11:59 p.m. ET on April 23, 2009. To access the replay, please dial 1-877-660-6853 (USA) or 1-201-612-7415 (international) and reference the account number 3055 and the access code 319008.

A live audio webcast of the call will also be available from the Investors section on the corporate web site at http://www.sinovac.com . A webcast replay can be accessed on the corporate website beginning April 9, 2009 and the replay will remain available for 30 days.

About Sinovac

Sinovac Biotech Ltd. is a China-based biopharmaceutical company that focuses on the research, development, manufacture and commercialization of vaccines that protect against human infectious diseases. Sinovac's commercialized vaccines include Healive® (hepatitis A), Bilive® (combined hepatitis A and B), Anflu® (influenza) and Panflu(TM) (H5N1). Sinovac is currently developing a Universal Pandemic Influenza vaccine and Japanese encephalitis vaccine. Its wholly-owned subsidiary, Tangshan Yian is currently conducting field trials for the first domestically-developed inactivated animal rabies vaccines. Additional information about Sinovac is available on its website, http://www.sinovac.com . To be added to our distribution list, please email: info@sinovac.com.

    For more information, please contact:

Helen G. Yang	Investors:
Sinovac Biotech Ltd.	Stephanie Carrington/Amy Glynn
Tel:   +86-10-8289-0088 x871	The Ruth Group
Fax:   +86-10-6296-6910	Tel:   +1-646-536-7017/7023
Email: info@sinovac.com	Email: scarrington@theruthgroup.com
	aglynn@theruthgroup.com
	Media:
	Janine McCargo
	Tel:   +1-646-536-7033
	Email: jmccargo@theruthgroup.com