A magnetron is provided and includes a tube body with a plurality of communicated first cavities therein, a plurality of anodes in the first cavities including a cylinder and a plurality of vanes, outer ends of the vanes are connected with an inner circumferential surface of the cylinder; a first resonant cavity and a second resonant cavity are formed between the adjacent vanes, the cylinder is provided with a plurality of coupling slots arranged at intervals and running through the cylinder to communicate the first resonant cavity with the first cavity; a plurality of cathode arranged in and coaxially with the cylinder; the cathodes and inner ends of the vanes are spaced apart; at least part of the cathodes are located inside vanes, and an output slot is defined on the tube body for communicating the first cavity with an outside.