Francis Henry "Jumbo Jack" Gardner (August 14, 1903 – November 26, 1957) was an American jazz pianist.

Gardner played locally in Denver in the early-1920s, including with Doc Becker's Blue Devils and Boyd Senter's band.

He moved to Chicago in 1923, where he led his own band in addition to playing with musicians like Wingy Manone, Jean Goldkette, and Gene Austin.

Moving to New York City, he began associations with Sandy Williams's orchestra and Harry James, but returned to Chicago early in the 1940s, where he led his own group.

He spent much of his later life playing in Dallas, Texas, where he died in 1957.