Aiming at the problem that the output flow of proportional valve controlled by the pilot flow of high-speed switch valve is affected by the change of load pressure,based on the characteristics of the main valve flow linearly amplifying the pilot flow,a pressure differential compensation method of the pilot valve was proposed to ensure that the pressure difference between the two ends of the pilot valve remained unchanged,so that the flow rate was not affected by the load,so as to achieve the stable output of the main valve flow.The differential pressure compensator was designed and its parameters were optimized.The results show that the differential pressure compensator between the pilot valve and the main valve can suppress the influence of load pressure change on the pilot flow,so that the flow rate of the main valve after linear amplification remains stable.By optimizing the parameters of the differential pressure compensator,the response speed of the output flow of the main valve is improved,and the fluctuation of the output flow of the main valve is reduced,which meets the demand of hydraulic control technology for the stable flow output of digital hydraulic valve.