The invention relates to a coupler, and discloses a double-edge structure speed regulating permanent magnet coupler for solving the problems that in an existing coal mine factory, a high-power induction motor is started in an on-load mode, due to the fact that the starting torque of the induction motor is small, when the starting torque is smaller than the load torque in value, on-load starting can not be achieved in a directly-starting mode, and an adopted controller of the motor is high in price. The double-edge structure speed regulating permanent magnet coupler comprises a driving shaft, an output shaft, a flange with a neck, a release bearing block, a release bearing, a first support, a second support, a first magnetism conducting driving disc, a second magnetism conducting driving disc, an electric conducting metal disc, at least three positioning columns, a plurality of permanent magnets and a plurality of air gap adjustment devices. The first support, the first magnetism conducting driving disc, the second magnetism conducting driving disc and the second support are sequentially arranged in parallel, and the permanent magnets are fixedly installed on the two opposite plate faces of the first magnetism conducting driving disc and the second magnetism conducting driving disc in the circumferential direction of the input shaft. The double-edge structure speed regulating permanent magnet coupler belongs to the technical field of speed regulating coupling driving.