Using a hydrological and hydrodynamic model coupled with SWMM and GAST models, numerical simulations were conducted on the main urban area of Changzhi City to analyze the characteristics of waterlogging in flood prone points and the causes were explored.The results show that the peak values of accumulated water volume and accumulated water depth at the flood prone points of the underpass in the study area are more affected by the rainfall recurrence period than those at the flood prone points of ordinary road surfaces.When the rainfall recurrence period increases from 5a to 100a, the peak value of accumulated water volume at flood prone points A, B, C, and D increases by 292.8%, 265.5%, 1281.3%, and 59.7%, respectively, and the peak value of accumulated water depth increases by 83.3%, 92.1%, 581.0%, and 31.3%, respectively.The impact of different rainfall recurrence periods on the peak time of accumulated water depth in different types of flood prone points varies.When the rainfall recurrence period increases from 5a to 100a, the peak value of accumulated water depth at point D appears 11 min earlier, while the peak value of accumulated water depth at points A, B, and C appears 20,84, and 40 min later, respectively. Keywords: urban waterlogging; flood prone point; underpass; accumulated water volume; accumulated water depth; Changzhi City 〖FL