WC-10Co4Cr is widely used as wear-resistant protection materials in aerospace, nuclear power, and other fields due to its high bond strength, excellent wear resistance, good corrosion resistance and no hydrogen embrittlement. However, there is relatively little research on the performance evolution of WC-10Co4Cr coating in high-temperature long-term environments. In this study, WC-10CoCr coating was prepared by High Velocity Oxy-fuel（HVOF） spraying. It was subjected to constant temperature heat treatment at 540 ℃ for different time to study the influence of oxidation behavior on its structures and properties. The phase composition, microstructure and microhardness evolution of the coating at different oxidation time were characterized using X-ray diffraction, scanning electron microscopy and microhardness tester. The results indicate that WC-10Co4Cr coating prepared by HVOF is dense and low porosity. During the spraying process, there is a small amount of decarburization reaction in WC. The average oxidation rate of WC-10Co4Cr coating at 540 ℃ is 0.043 7 g/(m2·h). After oxidation, oxidation products such as CoWO4, WO3 and Cr2O3 are generated on the surface of the coating. These oxides can prevent further diffusion of oxygen to a certain extent and slow down the oxidation rate. With the extension of oxidation time, Cr and Co and other elements inside the coating are oxidized continuously, the porosity of the coating increases, while the hardness of the coating increases first and then decreases with the increase of oxidation time.