Aimed at the problem of the common failure of Oring in hydropneumatic springs under low temperature and reciprocating movement,a friction calculation model of Oring was established based on finite element method.The law of the stress,contact width and friction varied with oil pressure under normal and low temperatures was studied.The results show that,under normal temperature,the stress,contact width and friction are increased with the increase of oil pressure,while under low temperature,the Von Mises stress,contact width are decreased and the contact stress and friction are increased with the increase of oil pressure.The Von Mises stress,contact stress and friction under low temperatures are far greater than that under low temperatures,when the oil pressure is larger than 12 MPa,the change rate of friction with pressure is increased.The increase of tensile force and friction caused by the glass transition of rubber material is the key reason for the failure of Oring under low temperature,which should be considered in practical use.