The present invention provides a disk drive of a compact size that can effectively utilize internal space within a disk drive and permit a straightforward arrangement of parts. The disk drive includes a disk holder that has a plurality of holder plates that individually hold disks, a drive unit that plays back disks, disk selectors that form a space above and below a desired disk by raising and lowering the holder plates; and a drive base that moves the drive unit into the space that is formed by raising and lowering the holder plates. The opening amount of the disk holder by the rise and fall of the holder plates, is fixed. The height of insertion of a disk into the disk holder is on an upper side between the highest holder plate and the lowest holder plate when the disk holder is open.