Air temperature change is one of important issues in the research of global climate change.The trend of annual and seasonal air temperature in different regions of China is various due to the influence of terrain and monsoon.Using the daily and annual average temperature from 1951 to 2010 as the basic data with the climate trend rate,the moving average method,and the M-K trend test and mutation analysis method,we analyzed the characteristics of the annual and seasons air temperature in Hanzhong City.The results showed that:(1)the average annual air temperature of Hanzhong City in nearly 60 years had the increasing trend, and the temperature tendency rate was 0.18℃/10 a,it experienced two periods:the cold stage before the mid-1990 sis and warm stage after mid-1990 s;(2)the decadal variability of annual average temperature displayed thegently increasing-decreasing-significantly increasing'trend,the temperature had the obvious mutation with the mutation time in 1999,the annual average temperature after mutation was 0.9℃ higher than that before mutation;(3)the average air temperature of the four seasons was obvious increasing since the 1990 s,and the air temperature after 1990 swas higher than the average temperatures of all seasons.The increasing rate of air temperature was greater in spring and winter than in autumn,and then in summer, however,it was less than the same period level in China;(4)the average air temperature of winter and spring in nearly 60 years had the obvious mutation with the mutation times in 1999 and 1997,respectively, however,it was not obvious mutation in summer and autumn.