Abstract: In this paper, the attenuation absorption and scattering effects of cloud and rain m microwave and, frequency:1-300GHz (wavelength:0.1 cm-30 cm),have been calculated. The rain rate statistics and analysis in Beijing District have been treated. The effects of cloud and rain on satellite-earth microwave communication are discussed. It is important for engineering design of satellite-earth communication. In this paper, a new method for prediction of the attenuation of satellite-earth microwave communication is given. It is more accurate and convenient for engineering design.