A motor includes a rotor module and a stator module. The rotor module includes a plurality of first magnet units, a plurality of second magnet units, a hollow magnetic conductance pillar and a rotating shaft. The first and second magnet units are alternately arranged to form a hollow pillar. An outer surface of the hollow pillar includes a plurality of first surfaces and second surfaces of the first and second magnet units. The first and second surfaces have different magnetic poles. The hollow magnetic conductance pillar and the rotating shaft are disposed in and through the hollow pillar and the hollow magnetic conductance pillar, respectively. The stator module includes a shell and a coil unit. The rotor module is disposed in the shell and the rotating shaft is extended out of the shell. The coil unit is disposed on an inner surface of the shell and around the rotor module.