The convective weather process influencing Shandong Province during the opening ceremony of the 11th Chinese National Games is simulated with the threedimensional numerical model developed by the Institute of Atmospheric Physics (Chinese Academy of Sciences), and the results of the simulation are analyzed. The results show that the simulated clouds are consistent with the observation clouds very well. Different seeding schemes with excessive AgI were designed, and the rainfall on the ground shows that the effectiveness of the seeding scheme with proper seeding position and initial seeding time was better. The comparison of natural clouds and simulated clouds is conducted，and the principles of rain dispersal are discussed. The AgI dosage and seeding location used in the simulation are almost consistent with those in the real operations, which can be used for reference in weather modification operations.