PURPOSE: To detect accurately skew in a simple constitution by counting the reproducing output by a counter, which corresponds to each track of multiple tracks, and subjecting the counted value to a logical processing.

CONSTITUTION: Counters C1, C2... corresponding to respective tracks of multiple tracks count reproducing outputs; and when counted values of counters C1, C2... reach a prescribed value, counters C1, C2... are reset by the output of OR circuit OR1 simultaneously, and the similar operation is repeated. In this case, in case of a little skew of counters C1, C2..., the output to OR circuit OR2 does not appear through counters C1, C2... where counted values are over a constant smaller than the prescribed value, and AND circuit AND does not generate the AND output. In case of a large skew, counted values of counters C1, C2... do not reach the constant, and the OR output is generated in circuit OR2 through counters C1, C2..., and circuit AND is opened, and the OR output of circuit OR1 is generated as the skew detection output from circuit AND, so that skew can be detected accurately in a simple constitution independently of the operation of a deskew memory.