The invention discloses an inner wind path structure of a permanent magnet wind driven generator. The inner wind path has an axial ventilation structure, and comprises a rotor axial ventilation hole, an air gap and a stator tooth ventilation hole. The shapes and the sizes of the rotor axial ventilation hole and the stator tooth ventilation hole are designed in combination with the wind quantity distribution condition of the three portions of the inner wind path and the temperature rise calculation condition, so that the temperature rise of each portion of a motor meets the designed requirement. In order to reduce the wind resistance of the inner wind path, an induced air plate is arranged on the inner wall of a base at the air outlet end of the inner wind path, meanwhile, the induced air plate is provided with ventilation holes to strengthen cooling of a bearing. By adopting the inner wind path structure, the effective space of the motor is sufficiently utilized, and the flow of the inner wind path is reasonably allocated; meanwhile, the wind resistance of the inner wind path is reduced, so that the temperature rise of each portion of the motor is roughly consistent; the power density of the motor is improved, and the size of the motor is reduced.