To provide a piezoelectric actuator exhibiting a greater displacement with a simplified drive circuit.

A piezoelectric actuator includes a piezoelectric structure layer in which any of two anti-electric field points in a hysteresis characteristic has an antisymmetrical polarization-electric field hysteresis characteristic located at the same electric field polarizy. The piezoelectric structure layer exhibits a greater displacement because the hysteresis characteristic is shifted only by application of a drive electric field with the same electric field polarizy. Since the amount of ink discharged can be increased and the speed of the ink discharge can be increased, it is possible to provide a printer with an excellent ink discharge efficiency.