Steenburgen was born in Newport, Arkansas; her last name is of Dutch origin. Steenburgen moved to New York City in 1972 to study acting.
 
 Steenburgen was married to Malcolm McDowell from 1980 to 1990, and has been married to actor Ted Danson since 1995. She won an Oscar for Best Supporting Actress for her role in the 1980 film Melvin and Howard. She played Clara Clayton in Back to the Future Part III (1990), a role which her children, fans of the Back to the Future movies, convinced her to play. She reprised the role by providing the character's voice in the Back to the Future: The Animated Series. She also had a role in the 1979 film Time After Time in which she played the love interest to H.G. Wells played by her then husband Malcolm McDowell. In both films, she played the love interest of a time traveller. She also starred in the sitcom Ink and the television miniseries of Gulliver's Travels with her husband Ted Danson.