In a double-stator motor has a rotary shaft, an annular rotor is coupled with a rotary shaft. First and second three-phase stators are arranged inside and outside to the rotor in the radial direction and formed to generate first and second rotating magnetic fields in response to three-phase currents, respectively. The rotor has an even number of segment poles made of soft magnetic material and arranged mutually separately at positions of the rotor. The positions are equally distanced apart from the rotary shaft in the radial direction and in the circumferential direction. Each of the first and second three-phase stators has magnetic poles which are the same in the number of poles as the segment poles and the magnetic poles are positioned such that magnetomotive forces from the magnetic poles are faced to each other between the magnetic poles of the first and second three-phase stators.