The utility model discloses a rotor of permanent magnet motor, establish in the epaxial rotor module of rotor and set up between adjacent two rotor modules and the cover is established at the epaxial spacer ring of rotor including rotor shaft, a plurality of cover, and the rotor module concatenates together through the spacer ring, evenly is provided with a plurality of radial ventilation holes along circumference respectively on the diaxon tip of rotor module, evenly is provided with a plurality of axial ventilation passageways along the axial in the rotor module, and the cooperation of axial ventilation passageway is radially ventilated the hole shape and is become axial, the radial wind path that circulates, the advantage is that axial ventilation passageway cooperation is radially ventilated the hole shape and is become axial, the radial wind path that circulates for this rotor of permanent magnet motor during operation, flow that the inside air current of rotor is not stopped through radially ventilate hole and axial ventilation passageway makes rotor surfaces's heat taken away by the air current, thereby has reduced the difference in temperature of different positions magnet steel effectively, has prevented magnet steel local overheat and demagnetizes, finally makes permanent -magnet machine's output performance reliable and stable.