A rolled-print-medium holder device includes an axial member, a holding member, an outer fitting portion, an inner fitting portion, and a weld portion. The holding member is fixed to at least one of both axial ends of the axial member and holds both sides of a rolled print medium. The outer fitting portion is provided at either one of the axial member and the holding member. The outer fitting portion has an inner peripheral surface. The inner fitting portion is provided at the other one of the axial member and the holding member. The inner fitting portion has an outer peripheral surface. The inner fitting portion is fitted into the outer fitting portion. The weld portion is provided at at least one of the inner fitting portion and the outer fitting portion. The weld portion at least fixes the outer peripheral surface to the inner peripheral surface by ultrasonic welding.