PURPOSE: To ensure a stable traverse control without using any speed reduction mechanism, by comparing the level of a signal corresponding to a tracking error signal with a reference level and using the output of comparison to control a gate circuit to the input of a stepping motor driving means.

CONSTITUTION: A tracking error signal TE given from a tracking servo loop consisting of a pickup 2 and a tracking servo circuit 4 is compared with reference levels 8a and 8b by comparators 8c and 8d respectively after passing through an LPF7. The output of comparison is fed to gates 10a and 10b and controls the input of a pulse given from a pulse generator 9 which is supplied to a stepping motor 11. The driving of a stepping motor 6 is controlled by the output of the motor 11, and then the position of the pickup 2 is controlled. This ensures a stable traverse control without using any speed reduction mechanism.