We aimed to evaluate the supply capacity and use status of the ecosystem in Miyun County. The potential and actual gross ecosystem products (GEPs), describing the background condition of an ecosystem and human demand for ecosystem products, respectively, were estimated. In 2020, the actual GEP of Miyun County accounted for 21% of the potential GEP. Water retention and climate regulation services were the highest in the potential and actual GEPs, respectively. The contributions of wetlands and forests were the highest in the potential and actual GEPs. Natural ecosystem area and vegetation coverage were the main factors affecting the potential GEP, whereas the actual GEP was mainly affected by gross domestic product (GDP) and population. Using Miyun County data, we quantitatively analysed the supply capacity and actual use of ecosystem products to clarify the interdependence between the ecosystem and human society to support decisions for regional eco-sustainability.