The wind tunnel test scheme of small size scaled vehicle models was designed and verified by computational fluid dynamics(CFD) method. By studying the wind tunnel test data and numerical simulation results, the reliability of the two methods and the application scope of the test scheme were defined. Based on the results of wind tunnel test and CFD, the difference of aerodynamic resistance of the four scaled vehicle models was demonstrated. By revealing the flow mechanism, the influence exerted by different style upon aerodynamic resistance was determined.