How to solve the contradiction between the social economy and the ecological environmental protection is a basic problem to understand the regional and urban sustainable development, which is manifested in the conflict space between urban sprawl and ecological protection. It's an essential conflict between the ecosystem of built-up and unbuilt-up areas. This article selects the Yangtze River Delta Eco-Green Integrated Development Demonstration Zone as the research area. Based on natural environment and socio-economic factors, we constructed a spatially quantitative evaluation model for urban sprawl risks to generate the spatial distribution of several risk areas and extract the serious risk areas of urban sprawl. Moreover, the ecological erosion index was used to identify and evaluate the ecological protection pressure space and extract the high value areas of ecological protection pressure. According to the overlapping space between the serious risk area of urban sprawl and the high value area of ecological protection pressure, the conflict degree between urban sprawl and ecological protection was analyzed for the coordinated relationship between the urban sprawl and ecological protection in the process of rapid urbanization. We aim to provide scientific and technological support for urban territorially spatial planning and regionally ecological protection decision-making. The results showed that: (1) the overlap space between the serious risk area of urban sprawl and the high value area of ecological protection pressure reached 583.83 km². The overlap area between the areas with higher urban sprawl risk and the areas with higher ecological erosion degree was 311.73 km² and the conflict degree was 53.39%. The overlap area of the highest risk area and the highest erosion area was 47.70 km², and the conflict degree was 8.17%. (2) In the demonstration area, the cultivated land ecosystem suffered the highest degree of urban sprawl conflict, accounting for 91.58% and 8.42% in the higher and the highest risk areas, respectively, followed by the grassland ecosystem. In order to coordinate the balance between urban sprawl and ecological protection, and ensure the sustainable development of the Demonstration Zone, this article further identified the ecological early warning area and key concern area in the demonstration area of integrated development of ecological green in the Demonstration Zone. In the construction of the key areas of urban sprawl, attention should be paid to the protection of the original areas under great ecological protection pressure, the ecological engineering construction should be strengthened, the scale of construction land should be controlled, and the proportion of blue and green space should be guaranteed.