The invention discloses an atomizer capable of preventing blockage of a high-melting-point substance in a nozzle and a flow guide tube. The atomizer is composed of a flow guide tube, a nozzle, a metal jacket, a ceramic circular ring, a metal sealing ring, metal circular rings, a heating body A, a gasket and the like, wherein a gap between the flow guide tube and the metal jacket is provided with the heating body A; a heating body B is arranged in each of gaps of the two Laval-structure air outlet tubes of the nozzle; the inner surface of the metal jacket is provided with a metal reflection film or a sprayed white reflection coating; the lower end part of the metal jacket and the lower end part of the flow guide tube are level and are in threaded connection with the ceramic circular ring; the end parts of the air outlets of the Laval-structure air outlet tubes of the nozzle are provided with the metal circular rings; and the end parts of the gaps of the air outlet tubes are in threadedconnection and sealed by the metal sealing ring. According to the atomizer capable of preventing blockage of a high-melting-point substance in the nozzle and the flow guide tube, the problem of blockage of the high-melting-point substance can be effectively solved, the atomizer has the advantages of simple structure, material saving and the like and is convenient to install.