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Due to the complexity of terrain of hilly mountains, in which areas are usually undulating, the body of hilly mountain tractors is needed to be balanced during work. Meanwhile, the suspension devices are needed to be adjusted in real time to adapt to the terrain changes. However, the open hydraulic system of quantitative pump was generally used currently by domestic ordinary small and medium horsepower tractor hydraulic suspension device, while the hydraulic system had a single output function and could not be operated simultaneously with the hydraulic suspension system, so that the compound operational demand of hilly mountain tractor hydraulic suspension system could not be satisfied. To solve this problem, hydraulic multi-point power output system, which was suitable for compound operation of hilly mountain tractors, was designed. Firstly, the mathematical model of the main hydraulic valve was established according to the working principle of the valve. Then, the overall design plan was done based on the simulation software, called advanced modeling environment of simulation （AMESim）, the system simulation model of tractor hydraulic multi-point power output was built. The results of simulation were as follows: when the load on the right side was changed stepwise, the adjustment time of system pressure was 0.1s, the overshoot was 2.13%, the two steady-state flows remained unchanged;when the right spool was changed stepwise, the right flow rate was changed from 7.2L/min to 13L/min, the adjustment time was 0.1s, the overshoot was zero, and the left flow fluctuation was very small. Finally, an indoor test was carried out, and the results showed that the designed hydraulic system had the function of load sensitivity, pressure compensation and flow distribution.