A head slider is related to an actuator block. A flexible printed circuit board is received on the surface of the actuator block. A head IC is mounted on the surface of the flexible printed circuit board. A heat conductive member is mounted on the head IC. The heat resistance of the heat conductive member is set smaller than that of the flexible printed circuit board. A larger amount of heat can be transmitted from the head IC to the actuator block. The actuator block is made of a metal material such as aluminum. The heat resistance of the actuator block is apparently smaller than that of the flexible printed circuit board. A larger amount of heat can be radiated from the actuator block as compared with the flexible printed circuit board. The head IC is thus reliably prevented from a rise in the temperature.