Abstract: This paper aims to study the evolution characteristics of Shanxi’ s droughts & floods and analyze their seasonal variation in a systematic way. Based on each month’ s rainfall data of 38 meteorological stations in Shanxi Province from 1958 to 2013, the author used linear trend estimation, Mann- Kendall and Morlet wavelet analysis methods, to analyze the climate characteristics of Shanxi’ s rainfall. The results showed that: (1) Shanxi’ s rainfall varied from 377.6 mm to 600.2 mm from 1958 to 2013, it increased progressively from the north to the south, was less in the central than in the east & west, and more in the east than the west; (2) in spring, the rainfall range was 55.7-107.4 mm, increasing from north to south, had longitudinal distribution in north-central and zonal distribution in south; in summer, the rainfall range was 230.1-355.6 mm, high values were concentrated in east; in autumn, the rainfall range was 76.6-157.7 mm, had obvious zonal distribution feature, high values were concentrated in southeast; in winter, the rainfall range was 5.1- 24.4 mm, the distribution feature was just like spring; (3) Shanxi’ s annual rainfall had a clear decreasing trend in the 56 years, the range was 12.6 mm/10 a; for the four seasons, the rainfall had a small increasing trend in winter, while the rainfall in spring, summer and autumn all had a decreasing trend; (4) Shanxi’ s annual rainfall had a significant mutation in 1967, the spring mutation years were 1965, 1982, 1992 and 2002, the summer mutation year was 1977, the autumn mutation years were 1969 and 2007, the winter mutation years were 1971, 1980, 1988 and 1991; (5) Shanxi’ s annual rainfall had 3 cycles: 7 years, 15 years and 26 years; Shanxi’ s spring rainfall had 2 cycles: 7 years and 24 years; Shanxi’ s summer rainfall had 3 cycles: 4 years, 8 years and 18 years; Shanxi’ s autumn rainfall had 2 cycles: 2 years and 8 years; Shanxi’ s winter rainfall had 2 cycles: 4 years and 15 years.