Abstract: The spatial differentiation and correlation of tourism environmental carrying capacity exist objectively, and scientific evaluation of the carrying capacity and formulation of spatial management and control policies are important ways to promote the sustainable development of regional tourism. Utilizing the panel data of 26 cities in Yangtze River Delta Urban Agglomerations from 2000 to 2018, the evaluation index system of tourism environmental carrying capacity based on DPSIR theoretical model was established by comprehensively considering economic, social, resource and ecological factors which were incorporated into the Driver-Pressure-State-Impact-Response system. The spatial auto-correlation method was applied to reveal the spatial correlation characteristics of tourism environmental carrying capacity of Yangtze River Delta Urban Agglomerations, and then the spatial econometric model and partial differential decomposition method were used to analyze the spatial spillover effect of tourism environmental carrying capacity. The results indicated that: (1) During the study period, the tourism environmental carrying capacity of Yangtze River Delta Urban Agglomerations as a whole maintained a fluctuating upward trend, and showed a spatial distribution characteristics of “high in the southeast and low in the northwest”. (2) The tourism environmental carrying capacity showed strong spatial agglomeration and correlation characteristics, and the intensity of spatial correlation showed an “M” type change trend of “rising-declining-rising-declining”. (3) The tourism environmental carrying capacity had a significant positive space spillover effect, and every 1  Unit growth in a local city will lead to 0.637 Unit growth in neighboring cities. Economic development level, technological progress level, environmental regulation intensity and tourism industry agglomeration had positive direct effect on local cities and different degrees spillover effect on neighboring cities. In order to effectively explore the potential of capacity environmental carrying potential of Yangtze River Delta Urban Agglomerations in the new period, attention should be paid to the spatial correlation and spillover effects of tourism environmental carrying capacity between cities, give full play to the role of inter-city cooperation and linkage, and promote the rational spatial allocation of elements of tourism environment complex systems.