Using daily precipitation data from six national meteorological stations in Anshun City from April to September 1984 to 2023, as well as the second set of NCEP/NCAR reanalysis data. Using methods such as synthetic analysis, statistical analysis, Mann Kendall non parametric statistical test, and Morlet wavelet analysis, this study analyzes the climatic characteristics of precipitation during the flood season in Anshun City. The results show that the precipitation during the flood season in Anshun City exhibits obvious interdecadal variation characteristics, with a long period of 6-8 years and a short period of quasi 2 years. The average total precipitation during the flood season shows a characteristic of "more in the west and less in the east". The high value center of precipitation is located in Zhenning County, and the low value center is located in Pingba District. The spatial distribution characteristics of total precipitation with abnormal precipitation over the years are basically consistent with the distribution characteristics of the average total precipitation over the years, The high center of the total precipitation with abnormally young precipitation shifted to Puding County, while the low center shifted to Xixiu District, showing a characteristic of "more in the northwest and less in the northeast". The precipitation of six national meteorological stations in Anshun City in flood season is dominated by light rain, accounting for 70.26%, while the precipitation of rainstorm and above only accounts for 3.92%. In years with abnormally high precipitation, the 500hPa geopotential height anomaly field shows a negative anomaly center near the Ural Mountains, a positive anomaly in Siberia, and a north-south symmetric structure of "positive negative positive" in mid to high latitudes in Asia. Most parts of China have a negative anomaly, and the western extension of the subtropical high pressure in the Western Pacific is located at around 135 °E and in the positive anomaly zone. However, during the flood season, precipitation anomalies tend to be more severe, The 500hPa geopotential height anomaly field is basically opposite to the 500hPa geopotential height anomaly field in years with excessive precipitation anomalies, and the western Pacific subtropical high pressure is weak. Its western ridge point is located east of 142 °E and in the negative anomaly zone.