Abstract: Using the equivalent transmission line theory of radar wave propagation in the medium, the reflection coefficient and the related calculation formula of the radar wave are analyzed at the vertical incidence to Salisbury screen. Based on the MATLAB software, the panorama analysis method is used to discuss and design the electric constant, permeability and reflectivity of Salisbury screen at the isolation layer doped with nano rare earth oxides. The results showed that the optimization of magnetic loss plays an important role in the optimized design of radar absorbing materials.The isolation layer doped with nanometer rare earth oxide improves the performance of Salisbury screen for the radar wave absorption in the frequency band 2~18 GHz. The backward reflectance attenuation value is greater than 7 dB, which can meet the basic requirements of radar wave stealth in national defense and military.