Frank A. DeSimone (July 17, 1909 – August 4, 1967) was an American mobster who was boss of the Los Angeles crime family from 1956 to 1967.

[5] After Jack Dragna died of a heart attack in 1956, DeSimone was elected the third official Boss of the Los Angeles crime family.

Jimmy Fratianno believed DeSimone had rigged the election, and transferred to the Chicago Outfit after his release from prison a few years later.

When the large mob conference was raided by law enforcement, DeSimone was outed as a mobster, and his underboss was deported to Italy a few years later for being an illegal immigrant.

[citation needed] Jimmy Fratianno also blamed DeSimone in his 1953 extortion case for having been sent to Folsom prison on a six-year extortion conviction, after dealing with fellow con-artists James B. Modica (a man who 'bumped' slot machines and a liquor store owner in Tarzana) and Burbank liquor store owner Dominic Raspona.

During the later part of his life, he never went out during night, and lived with his elderly mother in middle class Downey, California.