Abstract: Ship radar is affected by the evaporation duct microwave transhorizon propagation over an ocean surface. Based on the radio wave scattered by a rough sea surface and sea surface height probability density function, a new radio wave propagation method is presented, which incorporates the shadowing effect by the wave elevations. In addition, it is compared with two other methods which do not consider shadowing using the modeling and propagation experiment data. The results indicate: 1) The modeling results show that the path losses are different as the computing frequency and wind speed increase, the losses of difference roughness surface handling methods can exceed 10 dB at the same location; 2) It is an important factor in evaporation duct radio propagation that account for the physical mechanism of shadowing from the roughness sea surface. And the effectiveness of this method is preliminarily proved by marine transmission test; 3) Using the experimental data, the results show that the evaporation duct can be better diagnosed using different evaporation duct model at difference atmospheric stability, when the air-sea temperature difference is positive, the PJ evaporation duct is recommended, otherwise, the NPS model is better. The results are useful for radio wave propagation and the inversion of atmospheric duct over the sea.