The multi-axle steering mechanism is the key part of the multi-axle steering vehicle, which can ensure the Ackerman steering angle when steering. Based on characteristics of steering and Ackerman theorem, the ADAMS software is used to build simulation model of the multi-axle steering vehicle, and carry on optimization design of the steering mechanism. Compared with the traditional design, this method enhances accuracy and efficiency of the steering mechanism design. The research results can be used as a reference for the optimization of the steering mechanism of other multi-axle vehicle.