Aimed at the problem of high friction resistance in a common multi-channel redundant O-ring axial dynamic seal for spacecraft,simulation and experimental research were conducted on factors such as sealing ring compression rate,surface friction coefficient of metal pair,and assembly status.The relationship between the compression ratio of the sealing ring and the friction resistance was obtained through the test.The friction simulation model between the rubber material of seal ring and the shaft hole was established,the possible relationship between the dynamic friction coefficient of O-ring and different metal pairs was obtained through analysis and simulation test,and the simulation results were verified through the shaft hole simulation test.The results show that the friction resistance increases nonlinearly with the increase of compression rate of O-ring,and the larger the compression rate,the more significant the increase in friction resistance.Therefore,reducing the compression rate of the sealing ring can effectively reduce friction resistance.The key factor affecting the friction resistance of the sealing structure is the friction coefficient between the shaft and the sealing ring.By coating a lubricating film on the surface of the shaft,the friction coefficient of the main shaft can be effectively reduced,thereby reducing the friction resistance.