Abstract:By using methods of linear regression,the Mann-Kendall test,inverse distance weighted spatial interpolation and wavelet transform,the characteristics of climate and the trend of droughts and floods were analyzed based on temperature and rainfall data collected from 70 meteorological sites in Sichuan-Yunnan region from 1961 to 2011.Results showed as follows:(1)Temperature presented an increasing change over the last 51 years in Sichuan-Yunnan region with the tendency rate of 0.21℃/10 a,and has a significant long-term warming trend with the warming trend coefficient as high as 0.71.The annual averaged temperature was affected most by the altitude with the lowest annual average temperature happened in Western Sichuan plateau and the highest in the Southern Yunnan Province.(2)In the past 51 years the annual precipitation showed an decreased trend in Sichuan-Yunnan region with the decreasing rate of 10.76 mm/10 a. The precipitation was influenced by the southwest monsoon and the altitude with the relatively low precipitation happened in West Sichuan Plateau and the surrounding area of the Southwestern Sichuan basin,relatively abundant in Sichuan Basin and the most abundant in Southwestern Yunnan Province.(3)Climate warming and drying trend was obvious in Sichuan-Yunnan region with a sudden warming change and rainfall reducetion occurred in 1997 and 1999 respectively and droughts and floods oscillation periods of 10-15 years and 28 years.The trends of disasters changed clearly from floods to droughts in Sichuan-Yunnan region.