A rotating disk storage device is provided with a charging filter capable of efficiently removing dust staying in the interior of the device. In one embodiment, a charging filter is disposed below a magnetic disk and on a bottom of a base. The charging filter has plural through holes by forming a fibrous electret filter medium in a pleat shape. The through holes are formed so as to face a flowing direction of air. Dust, which is moving together with the air flow, is polarized and is attracted to the charging filter. The charging filter can collect even very fine particles without causing such problems as clogging and pressure loss. The pleat portion, which forms the through holes, further exhibits an air flow uniforming effect.