Based on the hydro - meteorological data,combined with the methods of trend analysis,Mann - Kendall mutation detection,and Hurst index,the runoff change was analyzed under climate change and human activities, and the influence of glacier change was also discussed. The results indicated that the climate was changed to warming and wetting during 1950s - 2015. The temperature increased significantly,but the precipitation increased slightly. It was different for climate change between the mountains and plains. The increase of temperature and precipitation in mountains were obviously more than these in plains. In the future,the temperature will continue to rise rapidly,and precipitation will increase lightly. The annual runoff series showed a slightly decreasing trend with no obvious mutation point,at a rate of 0.11 * 10~8m~3 /10a. The impact of human activities on runoff change was minimal,and climate change was the main causes. From 1980s to 1990s,the periodic reduction of precipitation in mountain areas and the relatively stable state of glaciers caused continuous reduction of runoff, which reached the minimum in the late 1990s; After 2000s,the runoff increased significantly,the rapid increase of glacier meltwater caused by ongoing warming was the main reason,the increase in precipitation caused by climate transition also led to an increase in runoff.