Abstract: In order to solve the problem of covert target shape design under constraint conditions, a target shape optimization scheme based on mesh modelling is proposed. By discretizing the target surface into fine meshes, the optimization domain of each mesh node is solved for the constraints, and the scattering field is calculated and optimized using the method of moments and genetic algorithm, and the optimized model structure can be obtained after iteration of the algorithm. The optimization results show that the method reduces the radar scattering cross section of both targets by more than 12 dBsm on average within the given constraints and upper bounds, which can fine-tune the target structure and play an important role in the strict constraints, and provides a new scheme for the optimal design of the stealthy target shape.