The change trend of precipitation and runoff and the abrupt point of runoff in the upstream of Weihe River Basin(WRB) were analyzed. The contribution of climate change and human activities to runoff was quantitatively calculated, and the reason for the runoff variation in the upstream of WRB was revealed, which provided the basis for the management and development and utilization of water resources in the WRB. Based on the precipitation and runoff data during 1961-2015, the evolution laws of precipitation and runoff in the upstream of WRB were analyzed by using linear regression, Mann-Kendall test and double cumulative curve method. The results showed that the trends of the precipitation and runoff volume change characteristics in the upstream of WRB were decreased. The abrupt points were in 1970,1987, 1990 and 1993. According to the abrupt point, the base period for the upstream of WRB was 1961-1969. The quantitative analysis of the double cumulative curve method shows that human activities are the main factors which influence runoff reduction. On the whole, the impact of human activities on the contribution of runoff activity shows an increasing trend,the contribution rate of human activities on runoff is up to 98.32% during 2010-2015. Climate change has certain influence on runoff change, especially, the impact of climate change on runoff accounted for 22.52% during 1990-1999. The statistics show that multiple extreme drought events occurred in the WRB, which causes a drastic decrease of the precipitation in the upstream of WRB. The contribution of climate change to runoff changes in the upstream of WRB has increased.