An electric rotating machine, including a stator including circumferentially arranged stator teeth, inner and outer rotors disposed coaxially with the stator inside and outside thereof, an inner armature coil group including a plurality of inner armature coils wound on the stator teeth on a side of the inner rotor, the inner armature coil group being energized to drive the inner rotor, and an outer armature coil group including a plurality of outer armature coils wound on the stator teeth on a side of the outer rotor, the outer armature coil group being energized to drive the outer rotor. The inner and outer armature coil groups have electric connections between the inner armature coils and between the outer armature coils so as to prevent occurrence of magnetic interference between the inner and outer armature coil groups, respectively.