Weng Cheng-yi (Chinese: 翁政義; pinyin: Wēng Zhèngyì) is a Taiwanese mechanical engineer. Weng earned a doctorate in mechanical engineering from Rochester University. He joined the National Cheng Kung University faculty in 1980. Weng became president of NCKU in 1997. He was the inaugural chairman of the Aviation Safety Council, serving from 25 May 1998 to 19 May 2000. He was minister of the National Science Council from 20 May 2000 to 6 March 2001. Days after taking office, Weng was criticized by members of the Legislative Yuan for being unaware of council proceedings. An anonymous legislator accused Weng of plagiarism in June 2000. Later that month, health department director Lee Ming-liang panned several government officials for smoking, including Weng.