To realize the structure of a hard disk device by which non-repeating run out is reduced and a process for incorporating a hard disk into a base and a process for incorporating a carriage into the base can be performed separately.

A shroud member 70 is screwed to a space part 60 just at a part on the upstream side in the rotating direction of the hard disk 43 compared with the shaft 52 of the carriage 45. In a state before fitting the member 70, the hard disk 43 and the carriage 45 are incorporated and rotate-inserted, the carriage 45 is combined with the disk 43 and the member 70 is fitted.