Abstract: Using conventional meteorological observation, automatic encryption station and NCEP/NCAR reanalysis date, analyze the 16 August 2013 rainstorm in Fushun. The results showed that Fushun "8.16" Storm was a process of extreme precipitation, with the characteristics of large rainfall, long duration and wide range. The weather conditions of high humidity and low pressure maintained for 15 days before the process. The Mongolian cyclone, low-shear line, 500 hPa westerly trough and subtropical anticyclone were the major systems which affected the heavy rainfall. The water vapor was gathered by multi-directional airflow. The coupling between the convergence of the low-level jet at the left front and the divergence of the upper-level jet at the right rear provided the dynamic condition. For the water vapor flux divergence, it was convergence in the level and divergence in the upper level before the precipitation. With the start of the precipitation, the convergence center developed to the low level, the upper- level divergence and low- level convergence increased significantly, and the convective motion developed more intensive. The rainstorm was located at the top of the high energy tongue of the 850 hPa height pseudo-equivalent temperature field. The dry at upperlevel and wet at low level vertical distribution was unstable for the atmospheric stratification. The dry cold air at low level transferred to lower, triggering the release of unstable high temperature and humidity energy at low level. Topographic effects on precipitation were as follows: (1) The southwest flow uplift effect on the windward slopes; (2)The bell terrain convergence effect; (3) Hun River valley funneling effect; (4) Mountain blockade effect; (5) The bell terrain preconference effect; (6) Superimposed effects of five kinds of terrain.