Formosa Plastics Corporation (Chinese: 台灣塑膠公司; literally "Taiwan Plastic Company") is a Taiwanese company based in Taiwan that primarily produces polyvinyl chloride (PVC) resins and other intermediate plastic products. It is the corporation around which influential businessman Wang Yung-ching formed the Formosa Plastics Group, and it remains central to the Group's petrochemical operations. The president of Formosa Plastics Corp. (FPC) is Lee Chih-tsuen (李志村).

The company was founded in 1954, with a US$798,000 loan from United States aid agencies. The first PVC plant was constructed in Kaohsiung and production began in 1957. As of 2005, FPC is the largest producer of PVC resins in Taiwan. When FPC's American operations are also considered, the company's total PVC resin capacity is 2.83 million metric tons per year, the second highest in the world after Shin-Etsu Chemical, which has 3.55 million metric tons per year as of May 2010 (expanding to 3.85 million metric tons per year by the end of 2010).

Formosa Plastics Group (FPG, Chinese: 台塑集團) is a Taiwanese conglomerate of diverse interests, including biotechnology, petrochemical processing and production of electronics components. The Formosa Plastics Group (FPG) was founded by Wang Yung-ching (王永慶) and his brother Wang Yung-tsai (王永在) and is chaired by Lee Chih-tsuen.

The Formosa Plastics Group was formed in 1958 to reflect vertical integration of the PVC manufacturing process by the Formosa Plastics Corporation (FPC). Nan Ya Plastics Processing Corp. was formed to purchase PVC resins produced by FPC. A third member of the group, New Eastern Plastics Product, was formed to manufacture those processed resins into consumer goods. Nan Ya and New Eastern were later merged into a single entity, Nan Ya Plastics Corp., and upstream integration was achieved in the 1990s through the construction of an ethylene-producing naphtha cracking plant and a coal-burning power plant. In Taiwan, FPG has also diversified into many other fields, including textiles, electronics, medicine, skin care, automobile manufacturing, gasoline retail and petroleum refining. The complete list of constituent firms is below.