UMC Announces Retirement of Mr. Tony Yu as President of UMC-USA Office

Position to be filled by Mr. Jason Wang, vice president of UMC's Corporate Marketing division

HSINCHU, Taiwan, June 15, 2009 - UMC (NYSE: UMC; TSE: 2303), a leading global semiconductor foundry, today announced the retirement of Mr. Tony Yu, president of the UMC-USA office, effective immediately. Mr. Yu, who initially notified UMC of his plans to retire earlier this month, has been an integral part of UMC's management team over the years. He has served in many key positions including head of North American sales and will remain active as senior advisor to UMC-USA following his retirement. Mr. Jason Wang, vice president of UMC's Corporate Marketing division, will become president of UMC-USA.

With over 25 years of semiconductor industry experience in sales and engineering, Mr. Yu joined the UMC-USA office in 1997 as vice president of sales. He was in charge of overseeing new account development, and was promoted to president in 2007. Under Mr. Yu's leadership, UMC-USA experienced significant improvement in new business, revenue growth, and customer support.

Dr. Shih-Wei Sun, CEO of UMC, commented, "Tony's substantial contributions to UMC over his distinguished career have helped UMC grow into its current position as a global foundry leader. He has played an instrumental role in establishing strong business relationships with our North American customers, which now account for a major portion of UMC's revenue. We will miss Tony's endless loyalty and enthusiasm towards UMC, and wish him all the best in his retirement."

UMC has appointed Mr. Jason Wang to succeed Mr. Yu. Mr. Wang is a seasoned operations executive with more than 20 years of experience in the semiconductor industry. Mr. Wang was vice president of Operations for Trident Microsystems Inc., before joining UMC in 2008 as vice president of Corporate Marketing.

About UMC
UMC (NYSE: UMC, TSE: 2303) is a leading global semiconductor foundry that provides advanced technology and manufacturing services for applications spanning every major sector of the IC industry. UMC's customer-driven foundry solutions allow chip designers to leverage the strength of the company's leading-edge processes, which include production proven 65nm, 45/40nm, mixed signal/RFCMOS, and a wide range of specialty technologies. Production is supported through 10 wafer manufacturing facilities that include two advanced 300mm fabs; Fab 12A in Taiwan and Singapore-based Fab 12i are both in volume production for a variety of customer products. The company employs approximately 12,000 people worldwide and has offices in Taiwan, Japan, Singapore, Europe, and the United States. UMC can be found on the web at http://www.umc.com.