A rotor for an electric motor has an iron core and a winding wound about teeth of the rotor core. Slots are formed between the teeth to accommodate coils of the winding. The winding includes several layers of windings distributed in the radial direction of the rotor. Each winding layer has a plurality of coils with the coils of each winding layer being wound on the teeth in the circumferential direction of the rotor. The overall center of gravity of the winding layers is substantially positioned at the geometric center of the rotor. Thus the center of gravity of the entire winding is located substantially at the geometric center of the rotor, thereby preventing noise caused by unstable rotation due to the deviation between the center of gravity of the winding and the geometric center of the rotor.