In an ultrasonic motor wherein an elastic travelling wave is excited in a vibrating stator comprising a piezoelectric element and an elastic element thereby to drive and a rotor which is disposed to touch the vibrating stator with pressure by friction forces, an ultrasonic motor having high efficiency is obtained. In the present invention, the above-mentioned vibrating stator is substantially disk-type, electrodes being provided to the piezoelectric element are disposed in a form of two sets of concentric circles having different phases with respect to each other in a circumferential direction in which the vibration is travelling, and have a constitution which excites the vibrating stator by flexural vibration modes of second order or higher in a radial direction and of third order or higher in the circumferential direction, and also, are designed so that at least mechanical impedances seen from each electrode become equal. By superimposing standing waves of the flexural vibration which are excited by those two sets of electrodes, the flexural vibration is made to travel in the circumferential direction, thereby to obtain a driving force.