Abstract: A disk recording or playback device comprises a holder pivoted to a chassis and reciprocatingly movable between an open position in which the holder is raised for inserting thereinto a cartridge containing a disk and a closed position in which the holder is laid on the chassis, a kickout mechanism having an engaging piece engageable with the holder and biased by a spring to urge the cartridge in a direction of discharge from the holder, the kickout mechanism extending into the holder and pushable by the insertion of the cartridge against the spring when the holder is in the open position to bring the engaging piece into engagement with the holder, and a change-over lever pivotally movably provided on the chassis for releasing the kickout mechanism from engagement with the holder during the transition of the holder from the closed position to the open position. The pivot portion of the holder and a pivot portion of the change-over lever are provided on the same surface of one member mounted on the chassis.