A rotating shaft is equipped with an outer shaft, and an inner shaft that is inserted into a hollow interior of the outer shaft. A first end part of the inner shaft includes an extending portion that is exposed and extends from the outer shaft. The extending portion is positioned and fixed to the outer shaft by a positioning and fixing member. The positioning and fixing member includes a nut member that is screw-engaged with an outer circumferential surface of the extending portion, a locking sleeve surrounding the nut member, and a locking ring that engages with the nut member and the extending portion.