A disk drive device, wherein a screw shaft (22) continues to rotate even if the carriage (8) of the disk drive device is moved to a stop position to move forward a locking member (21) engaged with the screw shaft (22) by compressing a spring (25), whereby, since a guide bar (24) engaged with a carriage support part (23) is moved integrally with the locking member (21), a lock mechanism is operated to release the lock of a tray to a body frame.
