Clifton Ko (; born 6 August 1958) is a Hong Kong film director, actor, producer, and scriptwriter.
Clifton Ko graduated from Kwun Tong Maryknoll College, and entered the TV and film industry in late 1970s, first working with director Clifford Choi. In this period, he wrote Choi's No U-Turn (1981) and Teenage Dreamers () (1982), as well as John Woo's comedy Once a Thief (1991). In 1982, Ko entered Raymond Wong's newly founded Cinema City & Films Co., and directed his first film The Happy Ghost in 1984. The film series, like all his major works, is a slapstick comedy with moral teachings, family values, and optimism. Ko, together with the company, is prolific in making "Chinese New Year movies". Important titles include the family comedy series It's a Mad, Mad, Mad World (beginning in 1987); Chicken and Duck Talk, a collaboration with comedian/writer Michael Hui; the ensemble comedy series All's Well, Ends Well (beginning in 1992); and It's a Wonderful Life (1994).
During the 2019 Anti-Extradition Law Amendment Bill protests and the subsequent imposition of the Hong Kong national security law in 2020, Ko expressed support for the Hong Kong Police Force.