PURPOSE: To reduce a seek time even when the frequency of use of each of data is remarkably different in the data arrangement system for a disk to reduce the seek time by packing and storing again data on the disk from a head of data areas.

CONSTITUTION: A counter table 8 has an area corresponding to each of sectors 9-1-9-n, and the number of times of use of data (read number of times) stored in a sector corresponding to each area is stored. A file data management section 1 reads a content of the counter table 8 at data arrangement to obtain the number of times of use of data stored in each of sectors 9-1-9-n and the data stored in each of sectors 9-1-9-n on a magnetic disk 5 are packed from the head of the data area 9 in the order of much number of times of use. Since data with much number of times of use are gathered at the head part of the data area, the seek time is reduced and a data read speed is improved.