Abstract: In order to explore the specific impact process of anti oxidation coatings on the structure of iron oxide scales, evaluate the influence of coatings on the formation of iron oxide scales, and conduct in-depth research on their impact on the overall oxidation behavior of steel, a comparative analysis was conducted on the oxidation behavior of Q235 steel samples without coatings and after coating treatment under high temperature conditions.The research results show that as time goes on, the degree of oxidation deepens. As the temperature increases, the protective effect of the coating decreases. The coating used at 1200℃ shows obvious failure. When the coating fails at high temperature, infiltration into the iron oxide scale affects its density. According to XRD analysis, the proportion of high valence iron in the failed samples is higher, and the samples are more completely oxidized.