The plasma spraying gun mainly comprises gun body, insulator, gas spiral-flow ring, flow divider, anode nozzle, front pressure cap, cathode body, inner pressure cap, insulating cover and outer pressure cap, in which the anode nozzle is connected with gun body by means of inner pressure cap, the flow divider is fixed in the interior of gun body by means of tight fit, the gas sprial-flow ring and insulator are connected with gun body by means of inner pressure cap,and the cathode body is fixed in the interior of gun body by means of insualting cover, outer pressure cap and in sulator. Said invention adopts integrated structure design, its structure is compact and beautiful.