Abstract: A rotating device includes a stationary body, a rotating body formed with an opening encircling a rotation axis, a fluid dynamic bearing mechanism which supports the rotating body relative to the stationary body, and which has a portion at one end side fitted in and fixed to the opening, a support portion that protrudes from an outer circumference of the fluid dynamic bearing mechanism to support the rotating body, and an abutting portion provided at the rotating body so as to abut the support portion. The support portion includes a flange protruding outwardly in a radial direction from the outer circumference of the fluid dynamic bearing mechanism, and the abutting portion includes a step that is a recess which is formed along an open end of the opening and into which at least a part of the flange enters.