Kelly made his acting debut in an uncredited role in the 1939 biopic The Story of Alexander Graham Bell, opposite Don Ameche and Loretta Young. Later, on July 15, 1954, he played a gunfighter, cattleman, and bandit Clay Allison in the syndicated television series, Stories of the Century that was starred and narrated by Jim Davis.
Further, in his career, Jack Kelly appeared in the television series based on the 1942 film King Row. With the end of the series, Kelly featured in Forbidden Planet, She-Devil and made guest appearances on Fireside Theater, Schlitz Playhouse of Stars, Lux Video Theatre, and Gunsmoke series.
Later in 1962, Kelly appeared in the lead role in Red Nightmare, an Armed Forces Information Film which shows the aftermath of America that is overtaken by communists. This movie was delivered by Jack Webb. After this, Jack appeared in the Fenton Canaby Story based series, Wagon Train that aired on ABC television network.
Apart from acting career, Kelly was also active in real estate and politics. He began real estate in Huntington Beach in the Mid 1960s and moved there permanently in 1971. During 1980 to 1990, Kelly worked as the city councilman and mayor in Huntington Beach.
Talking about his personal life, Jack Kelly was an American by nationality and belonged to the white ethnicity. Kelly married his girlfriend May Wynn, an American actress on October 14, 1956. The couple couldn't continue their married life and divorced on 19, 1964.
After divorce with his first wife, Kelly dated an American actress and model Karen Steele. Later the couple separated, and Kelly married Ann Smith on October 16, 1969, in Las Vegas, Nevada. The couple is blessed with a daughter Nicole.
Kelly suffered a heart attack and died at Humana Hospital in Huntington Beach, California, on November 7, 1992, because of stroke.