From engineering point of view, semi-active suspension system can realize whole vehicle attitude control so as to improve driving safety. Based on the synthetically analysis of multi-axle vehicle kinematic characteristics requirements, a kind of whole vehicle attitude control method was put forward according to skyhook damping principle. At the same time, fuzzy logic method was adopted to monitor the ride quality. From the contrast analysis of six-axle vehicle simulation results, whole vehicle roll angle was reduced with the semi-active suspension in lane change and turn brake, the ride quality was also improved in random input experimental simulation.