Abstract: To scientifically analyze the ecological civilization construction in the Beijing-Tianjin-Hebei (BTH) Region since the 18th National Congress of the Communist Party of China (CPC), a comprehensive ecological civilization evaluation index system was developed based on the economy-society-nature complex ecosystem theory, comprising technological innovation, low-carbon development, ecological benefits, and green living. A comprehensive evaluation model based on the combined entropy weight-CRITIC weighting method was employed to analyze the spatiotemporal evolution pattern of ecological civilization construction, and a coupling coordination model was applied to examine the synergistic development relationships among various dimensions. Furthermore, a modified gravity model and an obstacle degree model were introduced to identify spatial correlation characteristics among cities and regional bottleneck factors. The main findings were as follows: The overall Ecological Civilization Comprehensive Index (ECCI) of the BTH Region increased significantly, yet notable regional disparities persisted. Beijing and Tianjin led in performance, and the whole region showed a spatial pattern of higher in the central area and lower in the northern and southern parts. Inter-city spatial linkages were strengthened, with clear proximity effects. While sub-indices across various dimensions generally improved, their growth levels varied considerably. Beijing and Tianjin scored higher in technological innovation and low-carbon transition; northern cities performed better in environmental governance, while southern cities excelled in resource utilization. The coupling coordination level within the region improved overall, with enhanced spatial agglomeration effects. The evolutionary trend aligned with the ECCI spatial pattern; however, the coordination gap among cities widened. Green living and technological innovation were the main obstacle dimensions, with their obstacle degrees increasing. In contrast, the obstacle degrees of low-carbon transition and environmental governance were low and showed a declining trend. Key obstacle indicators included per capita public transport trips, intensity of science and technology expenditure, per capita park green space, and the proportion of energy conservation and environmental protection expenditure. Different cities exhibited significant variations in dominant obstacle factors and their obstacle degrees. The study reveals that although the ecological civilization construction level in the BTH Region has improved as a whole, significant spatial heterogeneity remains, and development across dimensions is still unbalanced. Moving forward, it is essential to strengthen technological innovation capabilities, deepen coordinated environmental governance, promote green living, enhance resource utilization efficiency, and implement differentiated policies to accelerate high-quality regional coordinated development.