Abstract: In the paper, the structure of ice and its optical properties are discussed briefly. The relationships between optical constants of ice and temperatures in different spectral regions are estimated by using the classical polarization theory. Optical constants of ice form the ultraviolet to the middle infrared and in the range of the earth atmosphere temperature are computed. The results show that the influence of temperatures on optical constants of ice crystals of clouds should be considered in the theoretical calculations of scattering and radiative transfer in cirrus clouds