Provided is a rotor core of a motor, the rotor core, the rotor core including: a thin disk-shaped rotor core member; a shaft hole penetratively formed in a center of the rotor core member; a shaft press-fitted into the shaft hole; a plurality of magnet insertion holes penetratively formed at a position near to a periphery of the rotor core member for inserted coupling by a magnet; a plurality of teeth protrusively formed at an inner circumferential surface of the shaft hole, and a skived portion protrusively formed at a position corresponding to the plurality of teeth of the shaft, wherein the rotor core members are stacked each at a predetermined height, and the shaft is press-fitted into the shaft hole.