A precision positioning unit composed of a table on which an article is to be placed, a linearly movable rod which is connected with the table at one end and further connected with a rod actuating device at another end, in which the rod actuating device is capable of linearly moving the rod forward and backward, has the following characteristics: the rod is connected with the actuating device via cushion mechanism; and by the side of the rod is placed a rod movement control device composed of an elastic member, a ultrasonic transducer, and a ultrasonic emitting surface, in which the elastic member is constituted to push the ultrasonic emitting surface to a side surface of the rod when the transducer is inactive, and the transducer functioning to draw the ultrasonic emitting surface away from the rod when it is active.