A head assembly includes a suspension having a gimbal, a flexible printed wiring sheet having a plurality of conductor patterns and adhered to the suspension, first and second piezoelectric actuators mounted on the gimbal, and a head slider mounted on the first and second piezoelectric actuators. The first and second piezoelectric actuators are adhered to the gimbal at end portion adhesion portions symmetrical with respect to the center of pivotal motion thereof and are adhered to the head slider at end portion adhesion portions on the opposite side disposed symmetrically with respect to the center of pivotal motion similarly. Consequently, when a voltage is applied to the first and second piezoelectric actuators through the flexible printed wiring sheet, a couple of forces can be generated which vary the posture of the head slider only in one direction around the center of pivotal motion.