By means of the conventional weather charts, numerical simulation results and NCEP reanalysis data, 91 autumn precipitation events in Shandong Province from 2001 to 2008 are analyzed. The influencing factors, including lowtrough cold front, cyclone, typhoon, shear line, upper cold vortex, transversal trough, and southern trough, are also studied. In order to tackle the difficulty in graded precipitation forecasting, the precipitation induced by certain influencing weather systems are graded, and then the circulation features, the physical characteristics, and forecasting hints for certain grade precipitation induced by the same weather system are studied. The results provided reference for the refined precipitation forecast during the 11th Chinese National Games, and can also be used for reference in precipitation prediction service.