Using EOF decomposition,cluster analysis and correlation analysis,116-year annual mei-yu data of five stations in the mid-lower reaches of the Changjiang river are examined.Results show that the five stations data can represent typical mei-yu characteristics in this region.According to the relation between mei-yu rainfall and pentad rainfall,the 116-year mei-yu rainfall-concentrated periods are analyzed.The four different mei-yu parameters’ periods are analyzed by Morlet wavelet analysis.Laws of interannual and interdecadal variations and characteristics of trends are found.Climatic jumps are tested by the moving t-test.