Abstract: A more reasonable computational fluid dynamics (CFD)analysis is carried out for the external aerodynamic characteristics of the high-speedcar in this paper. The realizable k-\varepsilon turbulence two equationsmodel of RNS methods based on the FVM (finite volume method) combined withthe enhanced wall treatment method is apllied to simulate the externalflow field of a car model with tires, side mirrors and antenna and otherprotruding parts under vehicle's different speed conditions. The resultsshow that the difference of the vehicle surface pressure along the x-directionleads to the car's aerodynamic drag; with the increased vehicle's speed, thecar's aerodynamic drag grows faster than the aerodynamic lift.