An object of the present invention is to provide a small, high-power rotating electrical machine by suitably forming a distributed winding coil such that two stator magnetic poles each formed of in-phase coil turns are arranged within an electric angle of 360 degrees formed by magnetic poles of the rotor. The present invention provides a method for manufacturing a stator, the method including a first step of placing a distributed winding coil 207 composed of a wire wound around a reel 210, as a whole, inside a stator core 202, and a second step of moving an insertion blade 213 so as to spread the distributed winding coil 207 in the radial direction of the stator core 202, thus inserting the distributed winding coil 207 into a stator core slot 206.