Based on the daily precipitation data series measured by 133 representative rainfall stations in the Taihu Lake Basin from 1956 to 2018, P-Ш frequency analysis, Mann-Kendall test method, Morlet wavelet method and other methods are used to diagnose the precipitation evolution trend and statistical characteristics analysis. The results show that the annual precipitation in the Taihu Lake Basin increases slowly at a rate of 0.557mm/a from 1956 to 2018. The precipitation evolution characteristics of the Taihu Lake Basin and its water conservancy districts are inconsistent, and the precipitation fluctuations in the southeast plain area are greater than that in the northwest hilly area. The spatial distribution difference of design rainfall with 100 year return period is the largest among different frequency design rainstorms in each water conservancy district, with the largest 7d rainfall being the most significant, followed by the largest 3d rainfall, and the largest 1d rainfall being the weakest. The annual precipitation growth rate of each water conservancy district is different. The range in the northeast of the basin is 17.3～33.0 mm every 10 years, and that in the southwest is 3.30～22.2 mm every 10 years. The overall trend is gradually weakening from east to west. The annual precipitation in the Taihu Lake basin and its water conservancy subarea presents a multi-scale periodic change, with the most significant 35～62a periodic change.