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Over the last 5 decades, runoff from the upstream area of the Yongding River basin has greatly decreased because of changes in the climate and in the intensity of human activities. The Mann-Kendall rank correlation trend test, cumulative anomaly method, and double mass curve of precipitation and runoff were applied to analyse the hydrological sequence trends and altered features in the upstream area of the Yongding River during 1960-2010. The influences of climate change and human activities on changes in runoff were quantitatively assessed using a climate elasticity method based on the Budyko hypothesis. In this paper, the results showed that, on average, runoff in the 3 basins in the upstream area of the Yongding showed a significant (99% confidence level) downward trend. We found that human activities were the main driving factors for the decline in annual runoff in the Yanghe River basin, Sanggan River basin, and upstream area of the Yongding River basin, accounting for 82.04%, 81.51%, and 75.69% of the runoff reduction, respectively, during evaluation period I, and accounting for 77.94%, 72.73%, and 73.37% of runoff reduction, respectively, during evaluation period II. However, the impact of climate variability on runoff gradually increased over time in the 3 basins.