The invention discloses a miniature forced air cooling device of a permanent magnet power generator. The miniature forced air cooling device comprises a body, a base, a control box and a distribution box. The surface of the body is provided with a screen. The bottom surface of the body is provided with a base. The upper surface of the base is provided with threaded holes. The inside surface of the body is provided with a fixing frame. A motor is arranged on the fixing frame. The end of the motor is provided with a rotating shaft. The end of the rotating shaft is provided with blades. The forced air cooling device is advantageous in that the forced air cooling device automatically adjusts output power of the motor according to a heat amount of the permanent magnet power generator through a feedback control loop which is composed of a temperature sensing probe, a control host computer and a speed regulator; high convenience in use and effective prevention of unnecessary energy waste are realized; and furthermore un-thorough heat radiation is prevented.