In order to study the influence of the distribution of leading edge radius along the spanwise direction on the stealth and aerodynamic characteristics of flying wing layout, the spanwise distribution CST airfoil matching method is used to realize the parameterization of leading edge radius, and the multidisciplinary model output method based on mapping linkage is used to calculate and output numerical models with consistent shapes for aerodynamic and stealth disciplines. The experimental design method is used to construct sample points, the Kriging surrogate model is established, and the evolutionary algorithm based on the surrogate model is used to carry out single-objective and multi-objective optimization. Through the multi-objective optimization results of aerodynamic stealth with spanwise distribution of leading edge radius, it is proved that the forward radar cross section of stealth optimized shape can be further reduced by about 2 dB without losing aerodynamic characteristics.