A magnetic head assembly includes: a slider; an actuator disposed on an end face of the slider; and a magnetic head unit connected to the actuator. The actuator has a structure in which multiple electrodes are arranged in a piezoelectric body, and is driven in d33 mode. In other words, when a predetermined voltage is applied to the actuator, a portion between the electrodes in the piezoelectric body expands or contracts with respect to a voltage application direction. When the piezoelectric body of the actuator expands or contracts, the magnetic head unit is deformed, and the deformation causes a change of the distance between a magnetic head (recording element and reproducing element) and a magnetic recording medium.