The rotary electric machine and its manufacturing method

The invention provides a rotating electric machine which has good productbility without needing complicated equipment and excessive process. The rotating electric machine includes: a stator 3 and a rotor 4 which rotates departed from a rotating gap with respect to the stator 3, wherein the rotor 4 includes a rotor core 41 in which rotor plates punched from roll formed magnetic steel plate are laminated, and a spider 42 that retains the rotor core 41; the rotor plates and the rotor core 41 include a plurality of keys 41 arranged in their inner circumference contacting with the spider 42; the spider 42 includes a plurality of keyways 422 arranged in its outer circumference contacting with the rotor 4; a plurality of keys 42 of the rotor core 4 and a plurality of keyways 422 of the spider 42 are formed in such a manner that they fit with each other; and the plurality of keys 412 of the rotor core 41 and the plurality of keyways 422 of the spider 42 fit in a combination that renders a weight imbalance of the rotor core 41 due to lamination of the rotor plates and a weight imbalance of the spider 42 cancel each other.