Chapman was born February 2, 1953, in Denver, Colorado, the child of Wesley Duane Chapman (1930–2000), a welder (during Dog's childhood) later turned bail bondsman (after Dog started) with Aaron Bail Bonds, who served aboard the USS "Irwin" during the Korean War, and Barbara Darlene Chapman (; 1934–1994), an Assemblies of God minister. (more specifically, a Sunday school teacher) He has three siblings: Jolene Kaye Martinez (; 1955–2016), Michael Chapman, and Paula Hammond (). He is of German and English descent on his father's side, and of English descent on his mother's side.