In a disk rotation device, a box-type housing has an opening at one end, and a tray is attached to the housing and movable between a first position, located outside the housing, where the disk is placed on the tray and a second position, located inside the housing, where the disk on the tray is rotated. A plurality of locking units lock, when the tray is in the second position, the tray to walls of the housing where surfaces of the tray face the housing walls in a direction perpendicular to a movement direction of the tray.