The waverider is considered as an important candidate for the configuration of hypersonic glide vehicle (HGV) in terms of its high lift-to-drag ratio. Due to the severe aerodynamic heating, the sharp leading edge of waverider need be blunted, and the flow characteristics and the aerodynamic performance along the trajectory will change. In the current research, the flow characteristic of a HGV was studied based on a reference trajectory, and a numerical simulation was carried out to evaluate the performance of HGV with a blunt leading edge under a typical condition. The result indicates that the flow near the stagnation point exhibits three-dimensionality which cannot be approximated as a flow around a sphere or cylinder; the heat flux can be reduced and the aerodynamic performance of HGV may decrease as well when the leading edge is blunted: under the condition of 2 cm radii, the lift-to-drag ratio reduces by 12.34%, and different thermal protection methods can be used in different places of HGV.