Abstract: To investigate the distribution characters of the extreme precipitation, enhance regional disaster warning capabilities in Hunan, Jiangxi, Zhejiang, and Fujian provinces of south China with complex terrains, this study identify the daily extreme precipitation thresholds by percentile methods, and analyzed the spatiotemporal variations of the daily extreme precipitation thresholds, intensity, frequency, and the contribution to the total precipitation based on the ERA5 reanalysis and precipitation data from national meteorological stations in April to September from 1980 to 2020 and regional meteorological stations in April to September from 2016 to 2020 in the region of Hunan, Jiangxi, Zhejiang, and Fujian provinces. Finally, the relationship between the characteristics of daily extreme precipitation distribution and the distribution of geological and secondary disasters was discussed based on the published results. The results are as follows. (1) The daily extreme precipitation occurs mostly in eastern Fujian coastal areas, Poyang Lake Plain, and western Hunan hills, while light rains occur often in central Hunan Basin and northern Zhejiang-Fujian hills. Intensity peaks occur in June, with April showing the weakest intensity. (2) The daily extreme precipitation occurs more frequently in southeastern regions dominated by mountains than over plains in northwestern areas. The contribution of extreme precipitation to total precipitation show maximum (>35%) in northeastern Fujian coastal areas and minimum (<20%) in Nanling region. In June-July extreme precipitation contributes most to total precipitation in western Hunan hills and Wuyi Mountain Range (over 40%), while in August-September, extreme precipitation dominates along Zhejiang-Fujian coast.