The necking-in product is widely used in many fields in the world. An improved necking-in machine is introduced in this paper. Matlab/Simulink is the popular simulation software in the dynamic system simulation field due to its powerful computing capability. DSHplus is the hydraulic special simulation software with graphical programming environment and abundance of model libraries and the system model can be built quickly. The co-simulation of DSHplus and Matlab/Simulink can take the advantage of their merits, which can study the control algorithm that applied on the hydraulic proportional system better. The Fuzzy PID control algorithm can apply logistic inference to tune the PID parameters automatically according to the working condition, which can solve many engineering problem of high performance requirements. So the Fuzzy PID algorithm is applied in this paper to improve the performance of the hydraulic system.