A motor-installed roller (3) has a roller body (6) and a prime mover unit (35) installed in this body and composed of a motor (33) and a reducer (34). The roller body (6) has opposite ends closed with closures (7) serving as closures and having cavities (22) formed in it. An external force is applied to an area of outer periphery of the roller body (6), the area corresponding to and facing each cavity (22) so as to plastically deform portions of the roller body and the closure (7). A punched hook engagement (65) formed in this manner serves to easy consolidation of the closure (7) such as the closure, a bearing or the like and the roller body (6) into the motor-installed roller (3), in which they are protected from moving relative to each other in tangential and axial directions, also inhibiting the closure (7) from slipping off even if subjected to vibration.