Sunday Bloody Sunday is a 1971 British drama film directed by John Schlesinger, written by Penelope Gilliatt, and starring Glenda Jackson, Peter Finch, Murray Head and Peggy Ashcroft. It tells the story of a free-spirited young bisexual artist (played by Head) and his simultaneous relationships with a divorced recruitment consultant (Jackson) and a gay Jewish doctor (Finch).

Although a box office failure in many regions of the United States, the film received critical acclaim upon release, with major praise drawn towards Schlesinger's direction, performances of the cast (particularly of Finch and Jackson), and its screenplay. The film garnered significant praise for its positive depiction of homosexuality, marking a considerable departure from Schlesinger's previous film Midnight Cowboy (1969), which portrayed gay men as alienated and self-loathing beings, as well as other gay-themed films of the era, including The Boys in the Band (1970) and Some of My Best Friends Are... (1971).

The film received numerous accolades. At the 25th British Academy Film Awards, the film received eight nominations, winning a leading five awards, including for the Best Film. It received four nominations at the 44th Academy Awards: Best Director, Best Actor (for Finch), Best Actress (for Jackson), and Best Original Screenplay.