The supply and demand of ecosystem services are related to human's own well-being and human activities are the main factors affecting the supply and demand of ecosystem services. Coupling analysis of the two can provide a practical basis for improving the quality of regional ecological environment. In this study, based on the supply and demand evaluation of ecosystem services in the Qinling-Daba Mountains from 2000 to 2018, we constructed human activity intensity indicators and coupling ecosystem service supply and demand with human activities through a four-quadrant analysis model to explore the ecological and environmental quality status of the Qinling-Daba Mountains. The results showed that: (1) The surplus of ecosystem services in the Qinling-Daba Mountain area was abundant from 2000 to 2018, four ecosystem services were in surplus, and the variability of the spatial characteristics of supply and demand of ecosystem services became more and more obvious. (2) There was obviously spatial heterogeneity in human activity intensity, with human activity intensity gradually decreasing from east to west, with high value areas mainly in populated urban areas and low value areas in high mountain cold areas. (3) The ecological and environmental quality of a large area in the Qinling-Daba Mountain area was good, but 13.64% of the pixels and 20 counties were in the poor level of ecological environment quality. Through the implementation of ecological projects in recent years, the quality of the ecological environment in the Qinling-Daba Mountains has been greatly improved. Through the coupling study of ecosystem supply and demand and human activities, it can provide a certain reference for the regulation and management of mountainous areas and the improvement of ecological environment quality.