A disk drive including a main chassis; a tray on which a disk is to be removably mounted, the tray being installed to slide into/out of the main chassis, and including a pickup transporting unit that is configured to move a pickup base back and forth in a straight line in a radial direction of the disk. The pickup base includes an optical pickup installed thereon, The disk drive also includes a lock releasing unit that is arranged on the tray, is driven by receiving a driving force of the pickup transporting unit, and releases lock of the tray from the main chassis. The disk drive drives a lock releasing unit by using driving force of a pickup transporting unit.