Abstract: A piezoelectric actuator having a body with a front face, a rear face opposite to the front face, and second side faces opposite to one another, the body being formed by several active layers of piezoelectric material with internal electrodes intervening therebetween, wherein the internal electrodes include a first group of electrodes extending to the rear face of the body and connected to a first external electrode, and a second group of electrodes extending to the front face of the body and connected to a second external electrode, wherein the electrodes of the first group extend to the first side face of the block and are buried in the block near the second side face thereof, and the electrodes of the second group extend to the second side face of the block and are buried in the block near the first side face.