PURPOSE: To improve the reliability of the data reading operation of the disk storage device provided with a CDR system for making data line recording density uniform on the entire surface of a disk.

CONSTITUTION: A disk 1 is devided into plural zones Z1 and Z2, etc., each constituted of plural tracks T in a diameter direction and an empty area V equivalent to one track, for example, is provided between the zones. Formatting data is written into the track T on the line recording density constant within the zone and almost uniform for all the zones within the disk and a sector S is provided including a collating section ID. Thus, damages and reading errors generated by the erroneous writing of data in the track T located on the edge part of the adjacent zone are prevented by the collating part ID in the track T on the edge part of the zone.