A motor rotor equipped with a cylindrical rotor core formed by stacking multiple electromagnetic steel plates, end plates and balance weights stacked at both ends of the rotor core, and multiple headed swaging pins penetrating and integrally connecting the rotor core, the end plates, and the balance weights, wherein spacers or washers formed of a harder material than the swaging pins are interposed between the seating surface of the balance weights and the heads of the swaging pins. Thus, resistance of the motor rotor to excessive excitation force can be increased and a decrease in fastening strength can easily be prevented without changing the structure integrally fastened together by the swaging pins.