In order to improve the Y-ring sealing performance of the deep-sea special environment,the reciprocating motion was analyzed through the finite element simulation of contact stress and von Mise stress.The influence on maximum contact stress and maximum von Mise stress of Y-ring five section parameters was analyzed through orthogonal experiment,which included the root of the chamfering,the lip at the bottom,the angle of the lips,the radius of lip corner,the length of the lip.The results show that the chamfering at the root of the Y-ring has the greatest influence on the sealing performance,followed by the depth of the bottom of the lip,the angle between the lips and the radius of the fillet of the bottom of the lip.The influence of the three is basically the same,and the angle between the lips has the least influence on the sealing performance.An optimized structure of Y-ring was obtained.It is found that the maximum contact stress of the Y-ring after optimization is increased by 3.99%,the maximum von Mise stress is reduced by 20.50%.During the process from the sea surface to the deep sea for 5 km,the maximum contact stress and maximum von Mise stress of the Y-ring are better than before optimization,and the both increasing is less than 5%.The research has effectively improved the sealing performance and reliability of Y-ring in deep-sea environment,which has important engineering application value.