The integration design of the cartridge valve pilot control stage with movement of directional switching was researched. Based on single and double chamber components as actuators, an integrated design process for the pilot stage was researched. The whole process was illustrated with an application in the hydraulic system of injection machine. Results show that through integration of the pilot stage, the method is cost effective; it can reduce the complexity of the control system. The method proposed can be used further widely in other systems with function of proportional, directional, flow control and pressure control; it also can help building an intelligent design tool for hydraulic systems.