To prevent the runaway of a speed control system in a seek operation for the purpose of recovery of a track following operation without using a light beam moving direction detecting means.

A light beam spot is positioned in an objective track on an optical disk 1 by driving an optical head 4 with a positioning means 3. At this time, a track following control loop, a speed control loop and a means of impressing fixed acceleration by a kick pulse 34 are changed by a control loop changeover means 9, so as to perform each individual operation of the track following operation, the seek operation or the kick pulse impressing operation. When an off-track state is detected by an off-track detecting means 8 during the track following operation, a controller 10 is so operated that at the time of performing the seek operation for the purpose of the recovery of the track following operation by making a changeover to the speed control loop, the control loop is changed once to the kick pulse 34 immediately before performing this speed control, and the positioning means 3 is moved at prescribed acceleration in an arbitrary direction for a prescribed period of time.