Abstract: This invention provides an ultrasonic motor using a bolt-tightened Langevin type torsional vibrator as a stator. The stator produces a vibrational energy to be converted into a rotational energy for a rotor contacted with the stator. The rotor is provided between a piezoelectric actuator and the torsional vibrator so that the contact state between the rotor and the torsional vibrator is controlled either one of loose contact and tight contact therebetween. According to the present invention, since the piezoelectric actuator is slidingly combined to the rotor, the rotation energy is not applied to the piezoelectric actuator and thus the life time of the actuator becomes long.