Dennis Chan Kwok-sun was born in 1949 in Hong Kong, and he is the younger brother of renowned actor-director Philip Chan. While still in school, Chan began his entertainment career by performing with his band on a television variety show, which caught the attention of a RTHK director, leading to an audition invitation and subsequent regular appearances in TV dramas during the 1970s.
In 1977, Chan transitioned to becoming a producer for variety shows, and he made his film debut in Cop and Robbers in 1979, followed by over 90 films, mostly in cameo roles. He then starred in Krazy Kops in 1981 and Romantic Fool in 2007, and played significant parts in Soul in 1986, Cageman in 1992, and the American film Kickboxer in 1989, as well as its two sequels.
In 1984, Chan joined D&B as Distribution Manager, but left in 1987 to pursue film production at Hollywood. After returning to the Hong Kong film industry, he primarily worked in producing, writing, and directing. Notable films he produced or associate produced include The Wrong Couples in 1987, Hearts to Hearts in 1988, Naked Killer in 1992, and Future Cops in 1993.
Chan often doubled as a writer on films he produced, such as Remains of a Woman in 1993, which won the Best Actress award at the Golden Horse Awards for Carrie Ng, and Wild Horse from Shangri-La in 2009.
Chan made his directorial debut with Perfect Match in 1989, and also released Maybe Next Time in the same year. He directed the romance drama Love and Let Love in 1998. In 1993, he became the COO of Vehicle Of Light Film Company, and in 1999, he ran the China Culture Media Group Company, which produced programs on Chinese history and culture.
After a hiatus, Chan resumed his film production activities in 2006, producing and writing Air Diary, Wild Horse from Shangri-La, Besieged City, and directing The Romantic Fool, Wushu: The Young Generation, and 37.