Andrea King was born Georgette André Barry in Paris, France in 1919 to American Lovinia Belle Hart. At two months of age, she moved with her mother to the United States. She lived with her grandmother in Cleveland, Ohio, and Palm Beach, Florida, for the first four years of her life while her mother attended Columbia University in New York City. When her mother married Douglas McKee, King went to live with them in Forest Hills, Queens.

Andrea King appeared in Broadway plays and other theater work. Her Broadway credits included Fly Away Home (1935) and Growing Pains (1933). She also appeared as Mary Skinner in Life with Father. Her film debut was in a docudrama, The March of Time's first feature-length film titled The Ramparts We Watch (1940). In 1944, she signed with Warner Bros. and changed her stage name to King (some of her early movies have her credited as "Georgette McKee", her stepfather's name). King appeared uncredited in the Bette Davis film Mr. Skeffington (1944), followed by another ten movies in the next three years. The Warner Bros. studio Photographers voted King the most photogenic Actress for the year 1945.

According to her Los Angeles Times obituary, King was married to Lawyer Nat Willis from 1940 until his death in 1970. In her later life, she authored children's books and was active in Democratic politics.

She co-starred in the mystery-horror film, The Beast with Five Fingers (1946), and a drama, The Man I Love (1947), both opposite Robert Alda. King was originally cast to play Dr. Lilith Ritter in Nightmare Alley, a film noir directed by Edmund Goulding, but she chose instead the role of the sophisticated Marjorie Lundeen in Ride the Pink Horse (1947).

In the 1950s, King had leading roles in the film noirs Dial 1119 and Southside 1-1000 (both 1950) and a science-fiction story, Red Planet Mars (1952). She later played supporting roles in Hollywood feature films like The World in His Arms (1952) with Gregory Peck and Band of Angels (1957) with Clark Gable.

She made four guest appearances on Perry Mason between 1959–1963, including the role of murderer Barbara Heywood in the 1959 episode, "The Case of the Bedeviled Doctor". King continued to act on television until 1990 when she played her final role on the Murder, She Wrote episode, "The Fixer-Upper". She appeared twice more as herself on the A&E series, Biography, recalling her work with Peter Lorre and Montgomery Clift.

For her contribution to television she received a star on the Hollywood Walk of Fame in February 1960.

On April 22, 2003, King died in a hospice in Woodland Hills, California. She was survived by a daughter and three grandchildren.