Julianne Moore was born Julie Anne Smith in Fort Bragg, North Carolina on December 3, 1960, the daughter of Anne (Love), a social worker, and Peter Moore Smith, a paratrooper, colonel, and later military judge. Her mother moved to the U.S. in 1951, from Greenock, Scotland. Her father, from Burlington, New Jersey, has German, Irish, Welsh, German-Jewish, and English ancestry.
After studying theatre at Boston University, Moore began her career with a series of television roles. From 1985 to 1988, she was a regular in the soap opera As the World Turns, earning a Daytime Emmy Award for her performance. Her film debut was in Tales from the Darkside: The Movie (1990), and she continued to play small roles for the next four years, including in the thriller The Hand That Rocks the Cradle (1992). Moore first received critical attention with Robert Altman's Short Cuts (1993), and successive performances in Vanya on 42nd Street (1994) and Safe (1995) continued this acclaim. Starring roles in the blockbusters Nine Months (1995) and The Lost World: Jurassic Park (1997) established her as a Hollywood leading lady.
Moore received considerable recognition in the late 1990s and early 2000s, earning Oscar nominations for Boogie Nights (1997), The End of the Affair (1999), Far from Heaven (2002) and The Hours (2002). In the first of these, she played a 1970s pornographic actress, while the other three starred her as an unhappy, mid-20th century housewife. She also had success with the films The Big Lebowski (1998), Magnolia (1999), Hannibal (2001), Children of Men (2006), A Single Man (2009), The Kids Are All Right (2010), and Crazy, Stupid, Love (2011), and won a Primetime Emmy Award for her portrayal of Sarah Palin in the television film Game Change (2012). Moore won the Academy Award for Best Actress for her playing an Alzheimer's patient in Still Alice (2014) and was named Best Actress at the Cannes Film Festival for Maps to the Stars (2014). Her highest-grossing releases include the final two films of The Hunger Games film series and the spy film Kingsman: The Golden Circle (2017). She starred in the film Bel Canto (2018), After the Wedding (2019), and The Glorias (2020).
Aside from acting, Moore has written a series of children's books about a character named "Freckleface Strawberry". She is married to director Bart Freundlich, with whom she has two children.