A 3-DOF multi-axle steering vehicle model were established using Lagrangian analysis method, including steering system stiffness, cornering stiffness and power steering system. The vehicle model is verified correctly and universally by using front wheels steering vehicle model. Based on the vehicle model, the steady circling parameters of multi-axle steering vehicle are presented. The effects of vehicle physical parameters on the steering characteristics of multi-axle steering vehicle are analyzed. To further demonstrate the correctness of multi-axle steering vehicle model, a three-axle steering vehicle model were built by ADAMS software. It is a theoretical basis for the design of multi-axle steering vehicle and the evaluation of steering characteristics.