Mary Astor (born Lucile Vasconcellos Langhanke; May 3, 1906 – September 25, 1987) was an American actress. She is best remembered for her role as Brigid O'Shaughnessy in The Maltese Falcon (1941).

Astor began her long motion picture career as a teenager in the silent movies of the early 1920s. She eventually changed to talkies. At first her voice was considered too masculine and she was off the screen for a year. She appeared in a play with friend Florence Eldridge, and the film offers came in, so she was able to resume her career in talking films. Four years later her career was nearly destroyed due to scandal. In 1936 Astor was later branded an adulterous wife by her ex-husband, in a custody fight over her daughter. Overcoming these stumbling blocks in her private life, Astor went on to greater success on screen, eventually winning an Academy Award for Best Supporting Actress for her performance in The Great Lie (1941). Astor was a Metro-Goldwyn-Mayer contract player through most of the 1940s and continued to work in film, television and on stage until her retirement in 1964. Director Lindsay Anderson wrote of her in 1990 that "when two or three who love the cinema are gathered together, the name of Mary Astor always comes up, and everybody agrees that she was an actress of special attraction, whose qualities of depth and reality always seemed to illuminate the parts she played".

She also authored five novels. Her autobiography was a bestseller, as was her later book, A Life on Film, which was about her career.