The hydraulic pump of traditional hydraulic power steering system existed serious loss of pressure and flow. To solve this problem, the hydraulic power steering system based on loadsensing technology was designed. Loadsensing pump and hydraulic power steering system was established by using simulation software AMESim. The simulation results show that vehicles on straight driving conditions, the system shows the output characteristic of low voltage, low flow rate, and when vehicle need to steering, the system can according to the valve opening of rotary valve, quickly adjust the outlet pressure of the pump and flow which can meet the power demand. Then during vehicle running, the hydraulic power steering system based on load sensing technology can reduce energy consumption, achieve the goal of energy saving.