Tsai Ming-liang (Chinese: 蔡明亮; born 27 October 1957) is a Malaysian filmmaker based in Taiwan and one of the most celebrated directors in the Slow Cinema genre and the "Second New Wave" of Taiwanese cinema.

Tsai has written and directed 11 feature films and many short films and television films. The best-known are Vive L'Amour (1994, for which he won the Golden Lion), The River (1997), Goodbye, Dragon Inn (2003), and Stray Dogs (2013).

Tsai was born in Malaysia. He is of Chinese descent and spent his first 20 years in Kuching, Sarawak, after which he moved to Taipei, Taiwan. This, he said, had "a huge impact on [his] mind and psyche". "Even today", Tsai has said, "I feel I belong neither to Taiwan nor to Malaysia. In a sense, I can go anywhere I want and fit in, but I never feel that sense of belonging."

Tsai graduated from the Drama and Cinema Department of the Chinese Culture University of Taiwan in 1982 and worked as a theatrical producer, screenwriter, and television director in Hong Kong. From 1989 to 1991, he directed several telefilms. One of these, Boys, starred his muse, Lee Kang-sheng.

Tsai's first feature film was Rebels of the Neon God (1992). A film about troubled youth in Taipei, it starred Lee as the character Hsiao-Kang. Lee went on to appear in all of Tsai's feature films as of 2023. Tsai's second feature, Vive L'Amour (1994), is about three people who unknowingly share an apartment. The film is slow-paced, has little dialogue, and is about alienation; all of these became Tsai's trademarks. Vive L'Amour was critically acclaimed and won the Golden Horse Awards for best picture and best director.

Tsai's next film was The River (1997), in which a family has to deal with the son's neck pain. The family is similar to one that appears in Rebels of the Neon God and is played by the same three actors. The Hole (1998) is about two neighbors in an apartment. It features several musical numbers.

In Tsai's next film, What Time Is It There? (2001), a man and a woman meet in Taipei before the woman travels to Paris. This was Tsai's first film to star Chen Shiang-chyi, who starred in his next few films alongside Lee. Goodbye, Dragon Inn (2003) is about people inside an old cinema that is closing down. For this film, Tsai included even longer shots and fewer lines of dialogue than in previous films, a trend that continued in his later work. The Wayward Cloud (2005) is a sequel to What Time Is It There? in which Hsiao-Kang and Shiang-chyi meet again and start a relationship while Hsiao-Kang works as a pornographic film actor. This film, like The Hole, features several musical numbers.

Tsai's next film, I Don't Want to Sleep Alone (2006), was his first set in Malaysia and is about two different characters, both played by Lee. In 2007, the Malaysian Censorship Board banned the film based on incidents shown depicting the country "in a bad light" for cultural, ethical, and racial reasons, but later allowed it to be screened in the country after Tsai agreed to censor parts of the film according to the board's requirements. Tsai's next film, Face (2009), is about a Taiwanese director who travels to France to shoot a film.