Family spokesman Jason Lee said Hamlisch died Monday after a brief illness. Other details aren't being released.
Hamlisch's career included composing, conducting and arranging music from Broadway to Hollywood.
The composer won every major award in his career, including three Academy Awards, four Emmys, a Tony and three Golden Globes.
His music colored some of film and Broadway's most important works.
Hamlisch composed more than 40 film scores, including "Sophie's Choice," "Ordinary People" and "Take the Money and Run." He won his third Oscar for his adaptation of Scott Joplin's music for "The Sting." On Broadway, Hamlisch received the Pulitzer Prize for long-running favorite "The Chorus Line" and wrote "The Goodbye Girl" and "Sweet Smell of Success." A news release from his publicist said he was scheduled to fly to Nashville, Tenn., this week to see a production of his hit musical, "The Nutty Professor."
Hamlisch earned his place in American culture through his music, but he also had a place in popular culture. Known for his nerdy look, complete with thick eyeglasses, that image was sealed on NBC's "Saturday Night Live" during Gilda Radner's "Nerd" sketches. Radner, playing Lisa Loopner, would swoon over Hamlisch.
Hamlisch was principal pops conductor for symphony orchestras in Pittsburgh, Milwaukee, Dallas, Pasadena, Seattle and San Diego. He was to be announced to the same position with the Philadelphia Orchestra and also was due to lead the New York Philharmonic during its upcoming New Year's Eve concert.
He leaves behind a legacy in film and music that transcended far beyond notes on the page. As illustrative as the scenes playing out in front of the music, his scores helped define some of Hollywood's most iconic works.