Disclosed a rare-earth permanent-magnetic axial coreless generator with double magnetic circuits, including a main shaft, a coreless stator winding, an inner rotor structure connected with the main shaft and an outer rotor structure. The outer rotor structure and the inner rotor structure are spaced apart by the coreless stator winding and are connected with the main shaft; the coreless stator winding is arranged between the inner rotor structure and the outer rotor structure, to establish a generator structure with two magnetic field air gaps; when the main shaft drives the outer rotor structure and the inner rotor structure to rotate simultaneously under the action of an external force, a rotating magnetic field with double magnetic circuits is generated in the generator; and the coreless stator winding can simultaneously cut magnetic lines of the rotating magnetic field with double magnetic circuits by using contact surfaces inside and outside the winding.