The system composition and working principle of hydraulic motion control experimental bench which was used in laboratory were introduced，its closedloop force control system was described emphatically.On the basis of the AMESim element models which were established according to the actual servo proportional valve and hydraulic cylinder，AMESim model of closedloop force control system was given. The influences of different sampling time on the system were analyzed. Under two kinds of load condition including elastic load and non elastic load，dynamic response curves were analyzed. Finally PID controller was added to correct the system and a satisfactory result was gotten.