Driven by national strategies of new urbanization and ecological civilization construction, Chinese urban agglomerations have undergone profound restructuring in their territorial spatial patterns. Understanding the interactive feedback mechanisms between the evolution of territorial spatial patterns and ecosystem service values at the urban agglomeration scale is critical for optimizing territorial spatial resource allocation and advancing China's high-quality development. However, current research on the evolution of the territorial spatial pattern of Chinese urban agglomerations and its impact on ecosystem service value remains inadequate. To address this gap, this study employd the "production-living-ecological space" framework and constructed a long-term spatiotemporal dataset from 2000 to 2020 via a multidimensional analytical framework. This methodology integrated Standard Deviational Ellipse analysis, land use intensity, territorial spatial pattern indices, ecosystem services value (ESV) assessment, and geographical detector analysis. The research systematically investigated the evolution of territorial spatial patterns in Chinese urban agglomerations and evaluated its impacts on ESV. Key findings revealed: (1)Continuous expansion of living spaces alongside gradual contraction of production and ecological spaces, with decelerating rates of change. The directional bias in spatial distribution intensified. (2)A "concentric-radial gradient pattern" for land use intensity, exhibiting a decreasing gradient from the cores of urban agglomerations toward their peripheries. (3)Significant transformation of territorial spatial patterns: increased Edge Density and Landscape Shape Index, coupled with decreased Area-Weighted Mean Patch Fractal Dimension Index and Aggregation Index, indicating heightened spatial fragmentation. (4)ESV demonstrated a spatial pattern of higher values in the southeast and lower values in the northwest. Aggregate ESV increased over the study period, despite declines in specific regions. (5)Land use intensity emerged as the dominant driver of ESV changes. Factor interactions exhibited both bivariate enhancement and nonlinear synergy effects on ESV. This study provides a scientific foundation for optimizing territorial spatial patterns and enhancing ecosystem service values within Chinese urban agglomerations. The findings offer actionable insights for decision-making for promoting regional coordinated development and implementing high-quality development strategies under the "dual carbon" goals framework.