Aiming at the typical scenario of high pressure of return pipeline in the return pipeline caused by the continuous large flow output of hydraulic pump in the aircraft hydraulic system, dynamic pressure analysis model of safety valve downstream return pipeline was established based on AMESim software platform, and some hydraulic system components and parameters that may affect the dynamic pressure of safety valve downstream return pipeline were analyzed. The simulation results show that the fluid volume and fluid resistance effects of the components in the hydraulic system can reduce the dynamic pressure peak of the return line; the opening speed of the system safety valve has a significant impact on the dynamic pressure peak of the downstream return pipeline. When the opening time of the safety valve is within a certain range, the faster the opening speed of the safety valve is, the lower the dynamic pressure peak value of the return pipeline will be. When the opening time of the safety valve exceeds a certain range, the slower the opening speed of the safety valve is, the lower the dynamic pressure peak value of the return pipeline will be; the dynamic pressure peak value of the return pipeline is significantly reduced with adding the accumulator in the system. The larger the volume of the accumulator is, the lower the dynamic pressure peak value of the return line is, but the change is relatively small. The existence of the accumulator has a greater impact on the dynamic pressure peak of the return pipeline, but its volume has a relatively small impact. The simulation results can provide a reference for determining the design pressure of return pipeline in the early stage of aircraft hydraulic system design.