Computational analysis of a flow field around a complex geometry such as a vehicle configuration becomes more reliable with the use of the most current numerical method. And the flow field around a vehicle with tires and wheel houses is simulated with accuracy.Recent market trends necessitate the use of aerodynamic devices to improve aerodynamic characteristics of a road vehicle. However, due to their complex shape, few computational studies of these devices have been performed.In this paper, a computational analysis system for vehicle aerodynamics is established and it's reliability is discussed. As the effective application of the system, the contribution of movable aerodynamic devices is studied using the system. And the comparison of wind tunnel test results with computational results is desirable.