When the landing speed of the aircraft is fast,the rapid compression of the oilgas buffer will cause the pressure surge inside the buffer and efflux phenomenon at the damping hole.In order to reduce the pressure inside the buffer and the flow velocity of oil through the damping hole, taking the oil inlet velocity, the hole length, the hole diameter and the chamfer of the damping hole as the research object, the variation characteristics of the pressure and flow velocity in the buffer caused by the changes of various factors were analyzed by using the single factor method. Simulation calculation was carried out by using Fluent software. The results show that the greater the inlet velocity of oil is, the greater the pressure inside the buffer and the flow velocity are. The hole length has little influence on the pressure inside the buffer and more influence on the flow velocity of the oil in the damping hole; with the decrease of the hole diameter, the pressure inside the buffer and the flow velocity of the oil in the damping hole increase continuously;the chamfer has little influence on the pressure inside the buffer, but it is useful for reducing the flow velocity of the oil in the damping hole. The research results can provide reference for the optimal design of buffer.