Abstract: Different turbid media have different optical parameters such as absorption coefficient, scattering coefficient, anisotropic factor and refractive index. Monte Carlo method was used to simulate the influence of optical parameters on the transmitted photons for light transmitted through different atmospheres. The result shows that the temporal distribution of transmitted light has two peaks corresponding to ballistic photons and diffuse photons, respectively. Every optical parameter affects both the number and time range of ballistic photons, snake photons and diffuse photons. From the angle of statistical simulation, it is explained why atmosphere imaging is difficult when the refractive index of atmosphere is large.