The invention relates to an effective and practical technique in the field of heat treatment for metal materials in the power station tubing industry. Application of polymer high-temperature resistantcoating in metal material heat treatment includes blending phosphate aluminum power coating, silicone ceramic glass coating, the polymer high-temperature resistant coating, and the like and then brushing a tubing surface requiring heat treatment with the mixture. Contact between air and the surface of a metal material is effectively prevented in high-temperature heat treatment, thus inhibiting orreducing oxide skin shedding, surface crack generation, and other phenomena caused by severe oxidation of metal material surfaces.