Abstract: The 3-D flow numerical simulation of a hypersonic vehicle like X43-A was implemented,and the computational static pressure distribution on the undersurface was compared with the experimental data.The comparison shows that the numerical results are consistent well with the measurements.A study was carried out to investigate the aerodynamic characteristics and the full flowpath of the hypersonic vehicle in different flight conditions.Results indicates:(1) With the increase of the free stream Mach number,the full flowpath and the aerodynamic characteristics fluctuate though changes could be found.(2)Despite of the fact that the drag coefficient is not sensitive to the change of the angle of attack,the lift coefficient and the flow structure of the full flowpath is highly affected.(3)The sideslip affects the asymmetric flowpath but with little unfavorable influence on the aerodynamic characteristic.