An ultrasonic actuator includes: an actuator body using a piezoelectric element and generating a plurality of vibrations of different vibration directions; a driver element provided in the actuator body and operated in accordance with the vibration of the actuator body to output a driving force in a predetermined driving direction; a case containing the actuator body; at least one support rubber provided between the actuator body and the case to elastically support the actuator body along the driving direction with respect to the case; and at least one stopper provided between the actuator body and the case which comes into contact with at least one of the actuator body and the case when the actuator body is displaced in a direction opposite the driving direction such that the displacement of the actuator body in the direction opposite the driving direction is limited.