In order to study the influence of structural parameters of engine valve oil seal on sealing performance of oil seal,based on the finite element analysis,the structural parameters such as oil lip angle,gas lip angle,installation interference,lip fillet radius and spring stiffness were designed by orthogonal test,and the influence of oil seal structure parameters on the maximum contact pressure and radial force per unit circumference of valve oil seal lip was studied.Taking the maximum contact pressure and the minimum unit circumference radial force as the optimization objectives,the optimal parameter combination of valve oil seal was obtained.The results show that the fillet radius of oil seal lip has the greatest influence on the maximum contact pressure and radial force per unit circumference.The gas lip angle has a significant effect on the radial force per unit circumference,the oil lip angle has a strong influence on the maximum contact pressure of oil seal lip,but has little influence on the radial force per unit circumference.The spring stiffness has little influence on the radial force per unit circumference and the maximum contact pressure.Combined with the mean optimal level analysis,the combination of oil seal parameters meeting the optimization objectives was obtained.After optimization,the maximum contact pressure of the oil seal is increased by 85.61%,and the radial force per unit circumference is reduced by 20.54%.On the premise of ensuring the sealing performance of the oil seal,the wear condition of the oil seal lip is greatly improved,and the service life of the oil seal is improved.