The invention discloses a high-power microwave high-temperature smelting device. The device comprises a microwave energy generator, a microwave energy feedback system, a microwave energy application chamber, an external cooling system of the chamber, a furnace door trolley, a gas exhausting vacuum pumping system, a temperature detecting monitoring system and a thermal insulation protecting device, wherein the microwave energy generator can generate high-power microwave energy which can enter the microwave energy application chamber through the microwave energy feedback system and then can act on materials on the furnace door trolley; the external cooling structure of the chamber can ensure the reliability of the chamber wall when the materials are heated to be 1500 DEG C to work; the gas exhausting vacuum pumping system can balance the pressure in the chamber, and negative pressure can be generated in the chamber; the temperature detecting monitoring system can detect the temperature of the materials and the chamber wall, as well as monitoring the variation of the materials in a furnace; the thermal insulation protecting device has the thermal insulation protecting effect and can be used as a mounting support for a thermal insulation material. The device is reasonable in structural design, convenient to operate, fast to smelt, high in working efficiency, short in heating time, low in cost, green, environmentally friendly, high in safety performance, and wide in applicable scope.