The Big Boss (Chinese: 唐山大兄; originally titled as Fists of Fury in the United States) is a 1971 Hong Kong martial arts film directed by Lo Wei (who also wrote the film) and Wu Chi-hsiang. Bruce Lee stars in his first major film in a lead role, and his first Hong Kong film since 1960. The film co-stars Maria Yi, James Tien, Tony Liu, and Nora Miao. Originally written for Tien, the leading role was given to Lee instead when the film's original director, Ng Kar-seung, was replaced by Lo Wei. The film was a critical success and excelled at the box office. Lee's strong performance overshadowed Tien, already a star in Hong Kong, and made Bruce Lee famous in Asia and eventually the world.

The film went on to gross nearly US$50 million worldwide (equivalent to approximately $400 million adjusted for inflation), against a tight budget of $100,000, approximately 500 times its original investment. It was the highest-grossing Hong Kong film up until Lee's next film, Fist of Fury (1972).