Gaynor, among the last survivors of the so-called golden age of the Hollywood musical, died of natural causes in Los Angeles on Thursday morning, her long-time managers Rene Reyes and Shane Rosamonda confirmed in a statement to The Associated Press.
"As we celebrate her legacy, we offer our thanks to her friends and fans and the countless audiences she entertained throughout her long life," Reyes and Rosamonda said in a joint-statement. "Your love, support and appreciation meant so very much to her and was a sustaining gift in her life."
Her entertainment career spanned eight decades across film, television and the stage, but she is best remembered for her turn in "South Pacific."
The screen version of "South Pacific" received three Academy Award nominations, and won for best sound, while Gaynor was a best actress nominee for a Golden Globe.
Later in her career, Gaynor reinvented herself as a performing entertainer. Under the guidance of her husband-manager, Jack Bean, she starred in her own musical revue, earning top money in Las Vegas, Florida and theaters and auditoriums throughout the U.S. and Canada and in England and Australia as well.
Born Francesca Marlene de Czanyi von Gerber (Mitzi is diminutive for Marlene) in Chicago on Sept. 4, 1931, was a part of a musically inclined family, and she started singing and dancing at a young age.
Gaynor and Bean married in 1954 and in 1960 bought a spacious house in mid-Beverly Hills that became their home until his death in 2006. They rarely appeared at Hollywood events, preferring to entertain a few close friends. The couple had no children.