Abstract:The main urban area of Rizhao City is built along the coast. It belongs to the hilly area of eastern Shandong. The terrain is high in the northwest and low in the southeast. Rivers are distributed in a dendritic pattern, and flow from north to south into Futuan River and then enter the sea. In recent years, the flood disaster in the main urban area of Rizhao City shows the characteristics of urban waterlogging under the coupling of rainstorm, tide and flood. Based on 34 a of local measured rainfall data, the instantaneous unit hydrograph method and hydrological model method are used to study the coupling hydrological characteristics of rainstorm, tide and flood in this hilly coastal city, which can be used to guide the construction of local river flood control projects.