A method of detecting the echo intensity characteristics of moving targets under atmospheric conditions is proposed based on the atmospheric transmission model, atmospheric turbulence model and electromagnetic transmission theory in this paper. By setting light source and target parameters, the influences of atmospheric turbulence condition, target shape, incidence angle and detection condition on echo characteristics are obtained. Simulation results indicate that the echo intensity changes with different target shapes and incident angles. The absence of atmospheric turbulence conditions cause a more uniform variation in echo intensity compared to the presence of atmospheric turbulence conditions. Images gained from the study can invert the general shape of target. These provide a theoretical foundation for improving the probability of target recognition and detection accuracy.