Based on the WEP model and the water conservation capacity assessment formula, geographic detectors and scenario analysis were used to identify key factors influencing water conservation. The impacts of climate change and human activities on water conservation in the Yellow River water conservation area were quantitatively evaluated. The results show that the multi-year average water conservation capacity in the Yellow River water conservation area is 140 mm. The water conservation capacity in the region above Lanzhou has continued to increase, while it has consistently decreased in the southern tributaries of the Wei River and the Yiluo River Basin. High-value areas of water conservation are mainly distributed in the Qilian Mountains, the southern part of the Yellow River source region, the middle reaches of the southern tributaries of the Wei River, and the upper reaches of the Yiluo River Basin. Precipitation is the dominant factor affecting water conservation in the study area, while temperature, relative humidity, topography, and evapotranspiration also significantly influence its distribution, with synergistic effects among these factors. In the headwaters of rivers and lakes and in plateau mountain regions, climate change is the dominant factor affecting water conservation. In areas with intense human interference, particularly in central urban areas, water conservation is primarily influenced by human activities.