The “four pre” function system of intelligent water conservancy is one of the main implementation paths to promote high-quality development of water conservancy. Based on the author’s existing research,combined with dominating information technology,this paper takes Zhougongzhai reservoir as a case to study the dynamic rainstorm resistance capacity of large and medium-sized reservoirs. The results show that based on multi-source dataaggregation,through the research on intelligent analysis model of dynamic rainstorm resistance of large and medium-sized reservoirs and the establishment of business application system,dynamic intelligent calculation analysis andconvenient query display of rainstorm resistance can be realized,the calculation fineness of rainstorm resistancecapacity can be improved,and the application scope of rainstorm resistance capacity of reservoirs can be expanded.The research results can contribute to the development of“ four pre” system in reservoirs and basins,and support forfl ood control research and judgment,consultation and decision-making.