Provided is a piezoelectric actuator, which has an external conductor composed of a thick film conductor, does not easily generate conduction failure in the external conductor, and has excellent reliability. In a piezoelectric actuator (1), external conductors (5, 6) are formed on an external surface of a piezoelectric substance (2), and the external conductors (5, 6) are provided with a thick film conductor and a conductive reinforcing material (9). The thick film conductor is provided with a first thick film conductor (7) formed on the outer surface of the piezoelectric substance (2); second thick film conductors (8a, 8b) formed partially on the outer surface of the first thick film conductor (7), being brought into contact with the outer surface; and a conductive reinforcing material (9) bonded on the outer surfaces of the second thick film conductors (8a, 8b).