The present invention provides a rotary electric machine, in which positions in a diameter direction of a stator core and a housing can be set with a high accuracy, and a motor characteristic of the rotary electric machine can be prevented from deteriorating. In the rotary electric machine, a cylinder 04a of a ring component 04 is formed in such a way that a fitting outer surface 04c1 of the cylinder 04a of the ring component 04 is fitted to a fitting inner surface 02a of a first housing 02; a clearance value between the fitting outer surface of the cylinder and a fitting inner surface of the first housing is lower than a clearance value between an outer surface, in which the fitting outer surface is excepted, of the cylinder and an inner surface, in which the fitting inner surface is excepted, of the first housing; and a position in a diameter direction of a stator core 03 facing to the first housing is set by above-described fitting process.