The application of electrohydrostatic actuator(EHA-VSVP)system with combined rotating speed and displacement control in heavyduty manipulator was mainly studied. Based on the requirements of the heavyduty manipulator, the simulation models of hydraulic system and control system were established by using AMESim and MATLAB. In order to solve the problem of multiplying nonlinear coupling existing in the system, the control strategy of distributive decoupling was used，the system was simulated and analyzed by using the joint simulation technology of AMESim and MATLAB, and the stability of the system was explored from the perspectives of step response and sinusoidal response. The simulation results show that the principle of the designed EHA-VSVP system is correct and meets the performance requirements. The control strategy used by the system can be used to solve the nonlinear problem of multiplication, and the weight allocation has certain theoretical basis, which can meet the needs of control.