Abstract: The 15 kinds of ice crystal size distributions, 3 kinds of cloud heights and thickness, 30 kinds of ice water contents and 90 kinds of ice water path models for cirrus (Ci) and altostratus (As) are constructed, respectively. The single scattering properties of ice crystal particles, with sizes larger or smaller than 30 μm, are derived based on Mie theory and ray optical theory. The multiple scattering radiation transmission properties of the ice clouds for 4 kinds of ground surface albedos are calculated by using delta-Eddington method, and the new parameterization of ice cloud radiation characteristics is formulated. The formula can be used in climate model or atmospheric circulation model.