Disk drive having a rotatable lid and a disk insertion opening

There is provided a disk device that prevents entering of foreign matters, and that forms an opening/closing lid using an inclined surface of a front wall so that the disk device has a design according to which the thickness is not noticeable. A front wall 1a of an outer case 1 includes an inclined surface whose front part is inclined downward. An opening portion 1b is provided to the front wall 1a of the outer case 1, and a lid 2 that covers the opening portion 1b while allowing it to be opened or closed is provided. The lid 2 is configured to move, by rotating about a rotation shaft provided in a direction crossing a disk conveyance direction, between a closed lid position 2A in which the lid is flush with the inclined surface such that a disk insertion opening 1c is not exposed to the outside and an open lid position 2B in which the disk insertion opening 1c is exposed to the outside and a disk 200 is guided to the disk insertion opening 1c.