Martino died at his childhood home in the Philadelphia suburb of Springfield, in Delaware County, according to publicist Sandy Friedman, of the Rogers & Cowan public relations firm. Friedman didn't cite a cause of death.
Starting in 1952, Martino was known for hit songs including "Here in My Heart" and "Can't Help Falling in Love."
Besides acting in the Marlon Brando classic "The Godfather," Martino sang the 1972 film's title score, "The Love Theme From The Godfather." His Fontane character is a singer and occasional actor and is the godson of Brando's Mafia boss character, Don Vito Corleone.
The Italian-American crooner, born Alfred Cini, was one of a number of South Philadelphia-born singers, including Bobby Rydell, Frankie Avalon, Fabian and Chubby Checker. He also was a longtime resident of Beverly Hills, Calif.
Philadelphia radio and television personality Jerry Blavat dined with Martino and his wife on Monday night. Blavat told the Philadelphia Daily News that Martino appeared to be in fine shape and that he was shocked when he learned of the singer's death.
"He was the last of the show business legends," said Blavat, who has played Martino's songs on the radio for years. "There's nobody else. The last of the performers. A magnificent voice."