Ice clouds consist of ice crystal particles are an important part of atmosphere. Research on atmospheric radiative transfer properties under ice cloud condition is helpful to understand the role of ice cloud on atmospheric detection,ground air laser communications and so on. The difference of laser reflectivity propagation between the ice cloud atmosphere in the plane parallel mode with different solar zenith angle and the quasi spherical mode is compared by using the CDISORT method,the latest version of C language； The changes of laser reflectance propagation of atmospheric ice cloud with ice water content,effective radius,optical thickness,cloud bottom height,relative azimuth and other factors at the incidence of three laser wavelengths (0.65μm,1.06μm,1.55μm) are numerically calculated in quasi spherical mode. The results show that when the solar zenith angle is less than 70°,the relative error of laser reflectance propagation in the two modes is very small； when the solar zenith Angle is greater than 70°,the relative error of laser reflectance propagation in the ice cloud atmosphere will increases significantly under the two modes. The laser reflectivity propagation of ice cloud atmosphere decreases with the increase of effective radius and increases with the increase of optical thickness or ice water content. The mean albedo of ice cloud atmosphere varies greatly with different laser wavelength,but the mean value is greater than 0.8. The results of this paper provide theoretical support for satellite ground laser communication,satellite remote sensing and other engineering applications.