Abstract: The research about the rainstorm patterns is significant for the design of urban flood control and drainage. Firstly, the climatic and weather characteristics of long-duration rainstorms (6～24 h) were analyzed, and then long-duration rainstorms were classified to 7 patterns using the fuzzy identification method and objective identification method based on the 1-minute interval rainfall data of Panjin observatory, daily surface and upper synoptic situations data of East Asia at 8 and 20 from 1972 to 2023. Lastly, the characteristics of rainstorm disasters were analyzed too used disaster situation data from 1984 to 2023. The results showed that: (1) Long-duration rainstorms occured unevenly in different ages, and there were fewer heavy rainfalls in the first decade of the 21st of the 20th century. The duration of long-duration rainstorms typically spanned between 6～10 hours, and the events of more than 18 hours were relatively rare. Long-duration rainstorms with precipitation between 90～110 mm were the most frequent. (2) The synoptic situations of long-duration rainstorms could be classified as the northward-moving cyclones (42.3%), cold fronts (20.4%), large cyclones (28.7%) and Northeast cold vortexes (8.6%). (3) The long-duration rainstorms in Panjin can be divided into seven types of rainstorm patterns. The proportions of unimodal rainstorms, uniform rainstorms and bimodal long-duration rainstorms were 53.1%, 25.0% and 21.9% separately. The peaks of the most single-peak rainstorms were in the late and middle periods, the peaks of the most bimodal rainstorms were in the front and rear, in the front and middle. (4) IV (single-peak in the middle) and III (uniform) long-duration rainstorms easily accounted for severe waterlogging and flooding, and should be paid much more attention in flood control and drainage based on the analysis of disaster situation data combined rainstorm patterns in Panjin .