Mildred Dunnock (January 25, 1901 – July 5, 1991) was an American theater, film and television actress.

Born in Baltimore, Maryland, Dunnock was a school teacher who did not start acting until she was in her early thirties. After a couple of roles in Broadway productions, Dunnock won praise for her performance as a Welsh school teacher in The Corn is Green (1940). The 1945 film version marked her screen debut.

During the 1940s Dunnock performed mostly on stage, and scored another major success with Death of a Salesman in 1948. She reprised her role in the 1951 film version.

Her films include The Trouble with Harry (1955), Love Me Tender (1956), Baby Doll (1956), Peyton Place (1957), The Nun's Story (1959), BUtterfield 8 (1960) and Sweet Bird of Youth (1962). In addition to her successful career as a character actress in film and theater, Dunnock appeared frequently in numerous television series in guest roles, and later in her career, several made-for-television movies, including a remake of Death of a Salesman in which she played Linda Loman for the third time.

Dunnock was twice nominated for an Academy Award for Best Supporting Actress, for Death of a Salesman in 1951, and for Baby Doll in 1956.

Her final film was The Pick-up Artist in (1987). She died in Oak Bluffs, Massachusetts.

Mildred Dunnock has a star on the Hollywood Walk of Fame for her contribution to motion pictures, at 6613 Hollywood Boulevard.