To provide a disk clamping device which can reduce a required space for performing disk clamping in the disk device. The disk clamping device comprises: a pick arm 130 which is swung into and swung out of a space created by splitting trays 250 capable of housing a plurality of disks D; a drive unit which is mounted on the pick arm 130 and plays the disk D; a turning table 123 on which the disk D is mounted; a clamp arm 124 provided so as to be able to move up and down in substantially parallel with the disk D; and a clamper 125 which is attached to the clamp arm 124 and holds the disk D with the turning table 123.