Based on the hydrological data in the source region of the Yangtze River during 1960-2012, the mutation test was made using Mann-Kendall method. The result shows that the mutation point of the runoff is the year 2008. According to the mutation point of the runoff, the time series were divided into the periods of 1960-2008 and 2009-2012, and the relationship between the accumulative runoff, accumulative precipitation and time series were obtained. The contribution rates of precipitation and non -precipitation factors to the increase of runoff are 22.89% and 77.11% in the reach above the Tuotuohe Station. These contribution rates are 67.85% and 32.15% in the reach above the Zhimenda Station. The results of this study shows an increasing trend of the runoff in the source region of the Yangtze River.