he control performance of the Stewart parallel manipulator differs greatly depending on the so many different drive modes. Based on the structure analysis of the Stewart parallel mechanism, the control strategy of the hydraulic system has been analyzed and researched. The hydraulic control system of the parallel mechanism was built by AMESIM hydraulic analysis software, and connected in parallel by the Proportion Integral Derivative (PID) control and the H∞robust control strategy. The solved transfer function of the valve-controlled cylinder control system was applied to determine the superiority of the two control strategies by obtaining the varied displacement curve of the telescopic rod of the hydraulic cylinder. The results show that the tracking effect of H∞ robust control is better than PID control in the same frequency stage.