A new method for calculating the wall streamline distributions on hypersonic vehicles was presented.Firstly surface stream function was put forward,and the relationship between surface function with surface streamline was obtained.Secondly the boundary layer edge conditions were determined by 3-D CFD method and solved by 3-D Euler equtions.And finally,the wall streamline distributions were computed based on the stream function theory and flow parameters.The calculated results indicate that the prediction and the numerical simulation proposed are workable at small angle and without angle of attack.It will play an important role in exactly predicting the heating rates on hypersonic vehicles.