The Kuye River catchment is located in the soft sandstone area of the middle Yellow River where the ecological environment is extremely vulnerable. It is one of the principal sources of coarse sediment in the middle reaches of the Yellow River. The runoff and sediment load of the river have been changing considerably in recent decades. Therefore, it is of great significance for improving the catchment management of the middle Yellow River to explore the impacts of climate change and human activities on runoff and sediment discharge in the Kuye River catchment. In order to reveal the long-term variations of runoff and sediment discharge of the Kuye River, this study analyzed the runoff and sediment discharge series from 1955 to 2015 using non-parametric Mann-Kendall test and three kinds of abrupt change test, and estimated the contribution rates of climate change and human activities, respectively, using elasticity method based on the water balance model and double mass curve method. The results show that annual runoff and sediment discharge had a significant decreasing trend and the jump points occurred in 1996. The relationship between runoff and sediment discharge has changed significantly since 2012. Compared with the reference period (T₁: 1955-1996), the contribution rates of climate change and human activities to annual runoff reduction are 18.53% and 81.47%, respectively. The contribution rates of climate change and human activities to annual sediment reduction are 3.59% and 96.41%, respectively. Human activities, mainly vegetation restoration and coal mining, are the most important reasons that caused the reduction of annual runoff and sediment load in the Kuye River. Considering that intended and unintended human interferences in the Kuye River catchment have greatly reduced not only the sediment yield but also the inadequate water resource, it is a question of how to achieve ecological protection and high quality development by planning future soil and water conservation projects and adjusting the industrial structure in the context of global climate change with reference to previous governance effects.