In recent years, research on the relationship between urbanization and ecosystem services has aroused increasing attention. However, the relationship between the two at different scales remains unclear. Therefore, this study aims to investigate the relationship between ecosystem services and urbanization in Beijing, as well as whether and how this relationship changes over time and space. The study employs the InVEST model to quantify water supply, habitat quality, and soil conservation, while NDVI and MOD17A3HGF are utilized to quantify food provision and carbon storage, respectively. Additionally, domestic gross product (GDP), population density (PD), urban land proportion (ULP), and nighttime light intensity (NTL) are selected as urbanization indicators. Through hotspot analysis, correlation analysis, and generalized additive models, we analyze the linear and nonlinear relationships between ecosystem services and urbanization indicators (GDP, PD, ULP, and NTL). The results indicate that: (1) From 2000 to 2020, habitat quality and food provision in Beijing showed a declining trend, while water provision, carbon storage, and soil conservation exhibited an overall increasing trend. Simultaneously, GDP, NTL, and PD also displayed significant growth trends; (2) High values of water and food provision are mainly distributed in plain areas, while carbon storage, habitat quality, and soil conservation exhibit contrasting spatial distribution characteristics. High values of urbanization indicators are concentrated in the central and southern regions; (3) At the grid scale, with the increase of NTL, PD, and GDP, food provision and habitat quality showed a trend of initial decline followed by an increase, while carbon storage and water provision showed a trend of initial increase followed by a decrease. At the county scale, with the increase of urbanization indicators, food provision, habitat quality, carbon storage, and soil conservation overall exhibited a fluctuating declining trend, while water provision shows a fluctuating increasing trend. This study clarifies the impact of urbanization on ecosystem services and emphasizes the scale effect between urbanization and ecosystem service relationships, providing insights for ecosystem management in Beijing.