The dynamic analysis of each component of the system was carried out, and the mathematical model of the compound throttle speed control loop was established by using the state equation method. Based on Runge-Kutta principle, the loop characteristics were numerically calculated and analyzed, and the simulation model of the compound throttle speed control loop was established based on AMESim.The influence law of the area ratio of the inlet and outlet throttle valves, the external load on the hydraulic cylinder movement speed, the inlet and outlet pressure were obtained.The simulation results were consistent with MATLAB numerical calculation results.Experiments were carried out under different external loads. It is concluded that the hydraulic cylinder in the loop has good speed stiffness and stability.The research results provide reference for the design and optimization of the compound throttle speed control hydraulic system.