Ona Munson (born Owena Elizabeth Wolcott; June 16, 1903 – February 11, 1955) was an American film and stage actress. She starred in nine Broadway productions and 20 feature films in her career, which spanned over 30 years.

Born and raised in Portland, Oregon, Munson began her stage career in New York theater in 1919, debuting on Broadway in George White's Scandals. She starred in another four Broadway plays and musicals before the end of the 1920s. In 1930, she moved to Los Angeles to embark on a career in film, but after appearing as leads in several films, such as Going Wild (1930) and The Hot Heiress (1931), she returned to Broadway, starring in several productions, including Henrik Ibsen's Ghosts (1935).

Munson resumed her film career in the late 1930s, and was cast as madam Belle Watling in David O. Selznick's Gone with the Wind (1939), a role which became her most famous. She starred in numerous films for Warner Bros. in the 1940s, but was often typecast based on her performance in Gone with the Wind, for instance in von Sternberg’s The Shanghai Gesture (1941).

Munson married painter Eugene Berman in 1950, her second husband after a five-year marriage to director Edward Buzzell. She also had several documented affairs with women, including Alla Nazimova and playwright Mercedes de Acosta. Some commentators have considered her marriages as "lavender marriages", concealing Munson's homosexuality. By the mid-1950s, Munson was suffering from health complications following an unspecified surgical procedure, and frequently was using barbiturates. In February 1955, Berman found Munson dead in their Manhattan apartment, having committed suicide via a barbiturate overdose.