Diane Ladd (born Rose Diane Ladner; November 29, 1935 – November 3, 2025) was an American actress. She appeared in over 200 films and television shows, receiving three Academy Award nominations for her roles in Alice Doesn't Live Here Anymore (1974), Wild at Heart (1990), and Rambling Rose (1991), the first of which won her a BAFTA Award. She was also nominated for three Primetime Emmy Awards and four Golden Globe Awards, winning one for her role in the sitcom Alice (1980–1981).

Ladd's other film appearances include Chinatown (1974), National Lampoon's Christmas Vacation (1989), Ghosts of Mississippi (1996), Primary Colors (1998), 28 Days (2000), and Joy (2015). She was the mother of actress Laura Dern, with her ex-husband, actor Bruce Dern.