According to the two construction classification of hydropneumatic suspension,the advantages and structure of integrated hydropneumatic suspension were explained.Based on the basic assumption,the explicit mathematical expression of the dynamic force of the integrated hydropneumatic suspension was derived through the analysis of the relationship between the flow and the movement,the relationship between the damping hole pressure and the flow,the relationship between the pipeline pressure and the flow,and the gas pressure of each cavity.The filtering white noise method was used to describe road excitation of wheel.The integrated hydropneumatic suspension vehicle model was established by using the two degree of freedom model of vehicle body and wheel,and the vibration response variables were determined.The vibration of an integrated hydropneumatic suspension vehicle was simulated under the condition of B grade road surface and speed of 60 km/h.The results show that the integrated hydropneumatic suspension model and its vehicle model are effective and feasible for the simulation of vehicle vibration.