Williams married Valerie Velardi in 1978. They divorced in 1988. In 1989, Williams married Marsha Garces. She divorced him in 2008. Williams married Susan Schneider in 2011. Their marriage lasted until Williams' death in 2014. Williams had a son with Velardi. He had a daughter and son with Garces. His son, Zak Williams, is an actor, businessman, and filmmaker. His daughter, Zelda Williams, is an actress.