To provide the disk carrier adjustment structure of the main shaft motor of a disk device with which the balancing adjustment of a disk carrier can be performed more quickly and more easily.

A plurality of adjusting members and a plurality of positioning holes are included in the structure. These positioning holes are installed in a disk carrier or a rotor hub at equal angles and symmetry and the adjusting members are screwed into the positioning holes to be provided in the holes and they are formed so as to be brought into contact between the disk carrier and the rotor hub. Since the spacing between the carrier and the hub can be adjusted by changing extent of contact of the members, it is possible to keep the carrier and the hub horizontally and also it is possible to rotate the carrier stably and in a state in which the carrier is balanced.