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Due to ecological changes and human activities, the ecological environment has become extremely fragile with the soil seriously eroded. Rainfall erosivity (R) is an important parameter for forecasting soil erosion by using the USLE/RUSLE. However, there were few studies focusing on the suitability of simple R calculation models for Yunnan Province. Using the daily rainfall data from 1951 to 2010 in Kunming, a suitable calculation model of R for Yunnan Province were selected according to suitability analysis on five models which were commonly used in the southern parts of China, and the temporal and spatial distribution characteristics of rainfall and rainfall erosivity were also analyzed according to rainfall data collected by 36 meteorological stations distributed evenly in Yunnan Province. Through the suitability analysis, in the five kinds of rainfall erosivity calculation models, model B was the most suitable ones for Yunnan Province because of its better stability, the largest effective coefficient (Ef) and the smallest relative deviation (Er). Yunnan Province recorded an average annual rainfall of 1106.84mm, and the average annual rainfall of seven regions changed between 745.8mm and 1533.3mm.The distribution of rainfall in different seasons was not uniform, and the rainfall was mainly concentrated in summer which accounted for 53.97% of annual rainfall. Rainfall was unevenly distributed in different regions, which showed a decreasing trend from southwest to northeast in Yunnan Province. The average annual rainfall erosivity of Yunnan Province was 2719.31MJ·mm/(hm2·h), and the average annual rainfall erosivity of seven regions ranged between 1837.23MJ·mm/(hm2·h) and 3949.12MJ·mm/(hm2·h). The seasonal distribution of rainfall erosivity was uneven. Rainfall erosivity was concentrated in summer which accounted for 67.06% of annual rainfall erosivity. There was also a significant difference in the spatial distribution of rainfall erosivity, and it also showed a decreasing trend from southwest to northeast. The trend index of rainfall erosivity varied from -0.34 to -0.02,，which showed a decreasing tendency in nearly 60 years in different regions. This paper could provide some references for improving soil and water ecological environment and developing soil erosion models of Yunnan Province.