Based on temperature and precipitation datasets in the Bailong River basin during 1961-2010,the seasonal and inter-annual variation characteristics including tendency,fluctuation,mutation,period and persistence of temperature and precipitation were analyzed by using linear tendency and polynomial regression model,Mann-Kendall test,complex Morlet wavelet and R/S analysis.The results showed that the seasonal and annual mean temperature had a significant increasing trend during 1961-2010;the weak warming trend was detected before mid-1980s;the increasing rate of temperature was accelerated after a warming mutation in 1990s;the annual precipitation mainly experiencedhigh-low-high-lowfluctuations.The seasonal precipitation had similar fluctuations except for the winter.The precipitation increased weakly in the spring and winter,while decreased insignificantly in the summer,autumn and year.The temperature and precipitation had periodic variation of 7,11,22 a.The potential trend of seasonal and annual mean temperature would persistent.The precipitation in the summer and winter will increase,but decrease in the spring,autumn and year in the near future.