The influencing factors of the high temperature foam index of gasoline engine oil were analyzed based on the actual production of lubricating oil.According to the production data on the influencing factors,relating experiments were carried out to control the high temperature foam indicators within the range of qualified products and ensure the quality of oils.The experimental results show that the high temperature foam performance of the base oil has a direct impact on the high temperature foam performance of the product,which should be strictly controlled.The proper improvement of blending temperature and mixing strength can improve the high temperature foam performance of the lubricating oil.Adding the appropriate proportion of anti-foam agent can improve the product high temperature foam performance,but the influence effect of ways of adding and other factors is not obvious.In addition,it has the remarkable application effect when the test results and process control measures are applied in the actual production.