For flying-wing aircraft， the sharpening of the leading edge of the inner wing section can reduce the intensity of the specular reflection of the radar echo， thereby improving the stealth performance. Aiming at the aerodynamic problems caused by the sharpening of the leading edge， simulations are carried out on the flow field and electromagnetic scattering characteristics of a typical flying-wing aircraft. RANS equation is used as the governing equation， and the k-ω SST turbulence model is used to solve the problem. The aerodynamic performance of the flying-wing aircraft is analyzed， and the flow field characteristics are combined to explain. Using the multi-layer fast multipole algorithm， the simulation calculation of the electromagnetic scattering characteristics is carried out under the typical incident frequency. The results show that the leading edge sharpening modification of the inner wing section of the flying-wing layout aircraft can effectively reduce the forward radar cross section （RCS） and increase the penetration capability. But at the same time， it will bring about problems such as reduction of stall angle of attack under takeoff and landing conditions. By selecting an appropriate leading edge sharpening range， the situation can be improved， so as to have engineering application conditions.