A dynamic model of semi-vehicle under acceleration/braking condition based on air suspension was established. By applying wheelbase preview control to forecast the road surface roughness at the front wheel, the optimal controller based on wheelbase preview control theory was designed. Then the dynamic model was simulating with the MATLAB. The results show that both optimal control and optimal control with wheelbase preview can effectively reduce vibration of acceleration/braking system, which make an improvement in the vehicle’s ride comfort and handing stability. Finally, a controller based on wheelbase preview of air active suspension acceleration/braking system was designed, and then simulation was analyzed with white noise input. Centric acceleration, pitch angular acceleration and rear tire dynamic load of the back section were reduced significantly proving pre-wheelbase control can further improve the performance of the vehicle potentially, especially having an effect on decreasing the vibration of rear suppression.