Disclosed herein is a method for manufacturing a rotor, the method including an injection process of injecting a bonded magnet material into a cavity of a molding die generating a magnetic field in the cavity so that the bonded magnet material is poured into each of the magnet slots in the rotor core set in the cavity through one of openings of each magnet slot, wherein the molding die used in the injection process has gates which respectively open at positions corresponding to regions, each of which ensures a view from the one of openings to the other opening of the magnet slot along an axial center of the rotor core.