Finite element analysis software ANSYS was used to analyze the sealing structure of the rotary liner hanger bearing.The influence of seal ring geometry size on maximum contact stress and maximum equivalent stress was analyzed by using PDS module of ANSYS.It is found that the common parameters affecting maximum contact stress and maximum equivalent stress are lip angle,sealing ring width,seal ring length and root length of seal ring.The optimization design module of ANSYS was used to optimize the four common parameters,and the optimization sequence was obtained.After optimization,the maximum contact stress between seal ring and retaining ring is increased by 44%,and the maximum equivalent stress is decreased by 29.1%.