PURPOSE: To provide a reliable laminated piezoelectric actuator which does not give any to the life influence even when operated on a direct current or almost direct current drive voltage in a highly humid environment.

CONSTITUTION: Piezoelectric ceramic thin plates 1 and internal electrode thin films 2A and 2B, of almost the same shape as the plates, are alternately superposed and integrated to obtain a laminated body 3. Each of the four corners of these layers, composed of the ceramic plates 1 and internal electrode films 2A and 2B, which form four ridges parallel with the direction of the lamination, is chamfered or rounded. The corner ends of each layer, where microcracks are densely distributed, are thus removed; therefore, the resultant actuators will not cause short circuits between the internal electrode films 2A and 2B due to microcrack.