Abstract:With the annual mean temperature of 121 meteorological surface observation stations in Yunnan Province from 1961 to 2004,the spatial-temporal features of temperature variations in Yunnan is discussed.From the view of temperature variation of various decades,the fluctuation of temperature is slight in the 1960's decade and 1980's decade.The 1970's decade is the coldest one in the latest four decades.During the 1990's decade,the temperature turns higher gradually and the fluctuation of temperature in 1990's decade is considerable.Since 1980,average linear trend of annual temperature in Yunnan is warming up with 0.24℃ per decade,which is close to the average linear trend of main area of China.Baoshan,Zhongdian and Simao,which locate in the west of Yunnan,take on the fastest warming linear trend in the last 40 years,whereas the temperature's ascending trend of mid Yunnan is the most remarkable in the latest ten years.By using principal component analysis of factor fields,the larger value area of the first eigenvector is the sensitive area to the variation of temperature,and its time series is an index standing for the mean annual temperature variation of the whole province.The positive/negative areas of the second eigenvector correspond the lower/higher value areas of the first eigenvector respectively.In the higher value area of the first eigenvector,the feature of temperature variation possesses the character that the temperature is lower in the former time and higher in the latter time since 1960's decade,and the lower value area of the first eigenvector has reverse character.