Joseph "JS" Sica (August 20, 1911 – November 21, 1982) was an American mobster and member of the Los Angeles crime family who was involved in armed robbery, murder for hire, extortion, and narcotics distribution.

Originally from New Jersey, Sica mentored many West Coast mobsters, including Mike Rizzitello and Anthony "the Animal" Fiato.

However, the case was dismissed after Abraham Davidian, the prosecution's star witness, was shot to death while sleeping at his mother's home in Fresno, California.

During the 1950s, the Permanent Subcommittee on Investigations of the U.S. Senate Committee on Government Operations identified Sica as a prominent member of the Los Angeles crime family and an associate of mobsters Mickey Cohen, Salvatore Iannone, and Thomas DeMaio.

In 1961, Sica, Frankie Carbo, Frank "Blinky" Palermo and Truman Gibson Jr. were convicted in Los Angeles of conspiracy in connection with professional boxing.