A piezoelectric ultrasonic motor includes a piezoelectric stator including a hollow metal tube having a quadrangular cross section and four piezoelectric elements each installed in each outer face of the metal tube; a rotary shaft including a rotation bar inserted into an inner space of the metal tube, an upper rotation member provided around the rotation bar in contact with an upper surface of the piezoelectric stator, the rotation member rotating in response to the strain of the piezoelectric stator, a lower rotation member adapted to restrain the rotation of the rotation bar and contacting a lower surface of the piezoelectric stator and a power transmission member provided at one portion of the rotation bar to transmit the rotation of the rotation member to an object to be transported; and a power supply to apply a supply voltage necessary for the actuation of the piezoelectric stator.