Abstract:Supported by the Beijing Municipal Science and Technology Commission key project “Research on the hail suppression, rain mitigation operation during Olympic p eriod”, the technology of the rain mitigation operation during Beijing 2008 Oly mpic opening and closing ceremony was studied since 2002. The rain mitigation te chnological scheme, the rain mitigation working flow was made on the basis of t he study. 18 rain mitigation operation areas were designed according to the weat her characteristics and cloud moving direction during August and September in Be ijing Area, and the preliminary experiment results were also analyzed. Weather characteristics, seeding operation and the evaluation of the operation effect on 8t h August were mainly analyzed in the paper. It shows that the intensity of radar echo is weakened, the height of the radar echo is lowered and the area of inten se radar echo is decreased dramatically after the rain mitigation operation. Esp ecially after the seeding operation between 21:45-22:00, there was a gap obvious ly appeared in the radar echo. In addition, according to the change in the grade of the radar echo intensity we can see that the area of the strong echo was dim inished gradually, while the area of the weak echo was increased. The cloud top height and the cloud effective particle radius over the seeding place retrieved by the satellite also revealed the effect of the seeding operation.