A disk drive apparatus is constructed with a filter attached to an enclosure through a through hole formed in the enclosure. A special positioning operation is eliminated by inserting the filter into the through hole because a portion of the filter is exposed to the outside through the enclosure. The disk drive apparatus can be constructed so that the filter is supported on the enclosure. In this case, the enclosure has a chamfered portion around the circumference of the through hole; the filter has a flange corresponding to the chamfered portion; and the flange is brought into contact with the chamfered portion. The filter can be fixed to the enclosure by sticking adhesive tape on a circumference of the flange and a circumference of the chamfered portion of the enclosure. Adhesive residue is eliminated because the fixation of the filter is performed with single-coated tape.