On March 28, 1960, Franciscus married Kathleen "Kitty" Wellman, the daughter of film Director william A. Wellman. They had four children — Jamie, Kellie, Korie, and Jolie. After his divorce from Kathleen, he married the former Carla Ankney in 1980. They were still married at the time of Franciscus' 1991 death (he was a four pack a day smoker) from emphysema in North Hollywood, California, at the age of 57.