A piezoelectric actuator according to an aspect of the invention can include: a first actuator including a first piezoelectric driving part; and a second actuator including a second piezoelectric driving part. A central portion of the first actuator can be supported. The first actuator can be bent and deformed by applying a first driving voltage to the first piezoelectric driving part, so that both end portions of the first actuator can be displaced in a thickness direction of the first actuator. Both end portions of the second actuator can be coupled to the both end portions of the first actuator. The second actuator can be bent and deformed in the opposite direction to the first actuator by applying a second driving voltage to the second piezoelectric driving part, so that a central portion of the second actuator can be displaced in a thickness direction of the second actuator.