The utility model discloses a permanent magnetism gear drive, including stator assembly, magnet adjustment ring assembly, rotor assembly and casing assembly. The utility model discloses only have the one deck permanent magnet, consequently when practicing thrift the permanent magnet, the degree of difficulty of processing and assembly is also less. The utility model discloses a built -in type hole of permanent magnet in by rotor core is fixed, and the permanent magnet can be because of the high -speed centrifugal force that produces when rotatory of rotor core throws away, therefore safe and reliable. The utility model discloses a drive ratio can change as required. The utility model discloses an output speed can establish to invariable as required. The utility model discloses a last damping strip that is equipped with the conductor material and makes of rotor core can cut the magnetic field of stator winding production and form induced current, and the produced lorentz lorentz's power of this induced current can form the damping, makes rotational speed and torque fast convergence and steady operation after the rotor starts, the utility model discloses an air current can be taken away produced heat in stator assembly, magnet adjustment ring assembly and the rotor assembly.