"Clean & Green Watch 2007" Report Ranks UMC as the Top Semiconductor Company in Taiwan

Report conducted by the Asian Corporate Governance Association (ACGA) and CLSA Limited scores UMC 90 out of a possible 100

Hsinchu, Taiwan, December 17, 2007 - UMC (NYSE: UMC), a leading global semiconductor foundry, has been ranked as the top semiconductor company in Taiwan in the Clean & Green (C&G) Watch 2007 report conducted by the Asian Corporate Governance Association (ACGA) and CLSA Limited. The C&G Watch 2007 surveys and ranks environmental awareness of major Asian enterprises from top executives, the companies' understanding and response to environmental issues, the relevant policy declarations to investors and the surrounding communities, as well as the companies' future projections.

"We are excited to be recognized by ACGA and CLSA for our efforts and achievements in environmental protection and sustainable development," said Dr. Jackson Hu, UMC chairman and CEO. "This top-tier ranking again confirms UMC's position as a global manufacturing leader that has successfully integrated green manufacturing practices with sustainable long-term growth."

UMC ranked second overall out of 73 companies from Taiwan and third among the 336 companies surveyed in Asia. UMC's leadership in sustainable development has resulted in the company meeting or exceeding the requirements of government environmental protection laws as well as international standards. In 2006, UMC led the semiconductor industry in sustainable, environmentally friendly development by being the first semiconductor company worldwide to achieve QC 080000 IECQ HSPM Qualification, which stringent requirements go above and beyond the six listed materials in the RoHS guidelines to include the restriction of over 20 different hazardous substances.

About UMC
UMC (NYSE: UMC, TSE: 2303) is a leading global semiconductor foundry that manufactures advanced system-on-chip (SoC) designs for applications spanning every major sector of the IC industry. UMC's SoC Solution Foundry strategy is based on the strength of the company's advanced technologies, which include production proven 90nm, 65nm, 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 13,000 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.