The oxidation process of an aviation lubricating oil at different temperature and under the the catalysis of copper and iron was simulated by high temperature oxidation accelerator to investigate the law of high temperature oxidation of the aviation lubricating oil,the oxidation products were qualitatively and quantitatively analyzed by gas chromatography/mass spectrometry (GC/MS).The results show that the esters are the most abundant compounds produced by oxidation.At the oxidation temperature of 230 ℃,olefins begin to appear in the oil samples,and their content is increased and alcohols and acids appear as the temperature raises.Therefore,the temperature at which this lubricating oil starts to be oxidized violently may be 230 ℃.The acid value increasing and color deepening of the lubricating oil is mainly caused by the compounds produced from the consumption of additives.During oxidation process,some esters with long chain structure are changed into short chain structures,and small molecules like alcohol and acid appeare in the oil samples,which may lead to a decrease in lubricating oil viscosity.The decrease of antioxidant content and the production of unstable components will reduce the oxidation stability of lubricating oil,leading to the decrease of oxidation induction period and initial oxidation temperature.