Simulated oxidation tests of a domestic aviation lubricant and an imported aviation lubricant 50-1-4Φ at different temperatures were carried out by using ASTM D4636 standard oxidation stability simulator.The kinematic viscosity,antiwear performance and bearing capacity of the two lubricants after oxidization were analyzed and compared.The results show that,below the oxidation temperature of 175 ℃,the kinematic viscosity of the two lubricants is relatively stable,it can be used for a long time and the kinematic viscosity only has a slight increase with temperature.More than the oxidation temperature of 200 ℃,the kinematic viscosity of the two lubricants varies greatly with temperature and can’t be used for a long time.In the ultrahigh temperature environment,the viscosity of the two lubricants may decrease, which will be unfavorable to the formation of lubrication film.However,the domestic aviation lubricant can better adapt to the ultrahigh temperature environment in a short time.Oxidation has little effect on the antiwear performance of the two lubricants.After oxidation,the antiwear performance of the domestic aviation lubricant is slightly higher than that of 50-1-4Φ.Oxidation is beneficial to the improvement of the bearing capacity of the two lubricants.The bearing capacity of the domestic aviation lubricant is better than that of 50-1-4Φ after oxidation.