Abstract: Electromagnetic scattering and propagation in natural environment plays important role for defense hitechnology, such as radar surveillance, missile guidance, and target tracking etc. In order to meet the needs of monitoring and identification of targets in the ground-sea environment, first, we must study the electromagnetic scattering characteristics of the earth and sea environment; use the exponential distribution rough surface to simulate the height fluctuations of the transverse dune surface, and use the Monte Carlo method to simulate the windward slope, leeward slope of the transverse dune and the flat desert surface between the dunes. The general formula of soil moisture and dielectric constant proposed by Herkelrath is used to calculate the dielectric constant of sand. The FDTD calculation method is used to study the electromagnetic scattering characteristics of the transverse dune, and the angular distribution curve of the scattering coefficient is obtained. The influence of the height of the top of the sand dune, the horizontal distance between the windward slope and the leeward slope bottom to the top of the sand dune, the distance between the top of the sand dune, the angle of incidence and the sand moisture on the scattering coefficient are numerically calculated. The calculation results show that the height of the top of the sand dune, the horizontal distance between the windward slope bottom and the top of the sand dune, the distance between the top of the sand dune, the incident angle and the sand soil humidity have great influence on the scattering coefficient. The horizontal distance from the bottom to the top of the leeward slope has a complex effect on the scattering coefficient.