A rotor for an electric rotating machine includes a hollow cylindrical rotor core and a plurality of magnets. The rotor core has a plurality of magnet-receiving holes formed therein. Each of the magnet-receiving holes has a plurality of wall surfaces including a radially innermost wall surface which is positioned radially innermost among the plurality of wall surfaces. Each of the magnets is received in a corresponding one of the magnet-receiving holes of the rotor core. Further, each of the magnets is arranged in the corresponding magnet-receiving hole so that among the thermal resistances between the magnet and the plurality of wall surfaces of the corresponding magnet-receiving hole, the thermal resistance between the magnet and the radially innermost wall surface of the corresponding magnet-receiving hole is lowest.