The mechanical state and deformation of solid rocket motor (SRM) rubber Osealing ring under the storage conditions was simulated by using ABAQUS finite element software.Through the analysis of the leakage mechanism of SRM sealing structure,by introducing the rubber aging model into the molecular flow leakage model based on Roth sealing theory,the rubber O-ring leakage model under longterm storage was established.Some factors influencing the leakage rate of rubber O-ring were studied,such as storage time,compression ratio and roughness of flange surface.The results show that the stress of SRM rubber ring is distributed symmetrically as a dumbbell under the storage conditions,and the stress is concentrated on upper and down surfaces of the flange and rubber ring,right side wall of the groove.The leakage rate of rubber O-ring is increased with the increasing of storage time,and the leakage rate grows rapidly at the beginning along with time,but eventually becomes stable.The increase of compression ratio is beneficial to decrease the leakage rate of SRM seal structure.In the same storage time,the greater the roughness of flange surface,the greater is the leakage rate of rubber O-ring.