This paper explored the temperature variation in the region of middle reaches of the Yarlung Zangbo river valley of Tibet in China in past 51 years.The observed meteorological data during 1957 to 2007,including average mean temperature in annual,seasonal and daily times series,had been used to study the characteristics of temperature change trend using the linear statistical method and wavelet analysis method.It was showed that the annual temperature presented a significant increasing trend and the change r...