To provide a polishing device 1 capable of polishing a finishing portion 41 with a small diameter without giving a force in the bending direction.

An approximately cylindrical polishing portion 11 is filled with a polishing solution 30 and the finishing portion 41 is turned in the polishing solution 30 in the polishing portion 11 by a drive unit 20. The polishing solution 30 in the polishing portion 11 is circulated by a pump 60. Thereby, the outer peripheral surface of the finishing portion 41 is polished by a frictional force with the polishing solution 30 acting on the whole outer peripheral surface of the finishing portion 41. Therefore, the polishing device 1 which can polish the finishing portion 41 with the small diameter can be provided without applying a bending forth to the finishing portion 41 by pressing a lap plate unlike a conventional polishing device.