Wang Yung-tsai (Chinese: 王永在; pinyin: Wáng Yǒngzài; 24 January 1921 – 27 November 2014) was the younger brother of Wang Yung-ching, founder of Formosa Plastics Group.

[2] Wang began his business career by founding a lumber company in 1948, which he closed ten years later to help run Formosa Plastics.

[2] In 1993, Wang was named director of Formosa Plastics' naphtha cracker, the sixth processing plant of its kind in Taiwan.

[4] In 2010, Wang Yung-tsai was named #10 wealthiest person in Taiwan by Forbes.

[6] Wang Yung-tsai had three children and a granddaughter named Megan Chen who now goes to TES, and one wife.