This paper introduced the concept of regional L -moments analysis method via hydrometeorological approach, to precipitation frequency analysis, taking annual maximum rainfall data of 1d in the Taihu Lake Basin for an example. The 140 rainfall stations in the basin have been divided into 8 hydrometeorological homogeneous regions through four criteria, and applying three goodness-of-fit measures to the data, the best distribution has been chosen for each homogeneous region as GEV, GLO, GEV, GEV, GNO, GNO, GEV and GNO respectively, and the rainfall quantile estimates have been obtained through regional analysis method. The spatial patterns of rainfall quantiles are nearly the same for different return periods in the basin. The southwestern mountainous area exhibits to be a storm high risk area in the basin with potential threat of flash flood and debris flow disasters. The results show that regional L-moments analysis method is of academic and application values, and worth popularizing in the nationwide.