The invention relates to permanent magnet motors, in particular to a fully enclosed self-ventilation permanent magnet motor. The fully enclosed self-ventilation permanent magnet motor provided by the invention solves the problems of poor cooling performance, limited application range, large dissipation, low efficiency, poor operation reliability, complex structure and large volume of the existing permanent magnet motors. The fully enclosed self-ventilation permanent magnet motor comprises an engine base, a front end cover, a rear end cover, a front bearing, a rear bearing, a stator structure and a rotor structure; an axial main air inlet hole, a main ventilation gap, an axial ventilation hole and an axial main air outlet hole constitute a main cooling air path structure together; an axial auxiliary air inlet hole, an auxiliary ventilation gap and an axial auxiliary air outlet hole constitute an auxiliary cooling air path structure together; and the rotor structure further comprises a front rotor pressure ring, a rear rotor pressure ring, a round nut, a front permanent magnet baffle, a rear permanent magnet baffle, a front permanent magnet baffle pressure ring, a rear permanent magnet baffle pressure ring, a front balancing block and a rear balancing block. The fully enclosed self-ventilation permanent magnet motor provided by the invention is suitable for various fields.