At this stage, China is advocating the concept of ecological space protection, and optimizing the management and control of land development and utilization has become a basic consensus in space planning work. Firstly, this paper analyzes the key ecological issues on the basis of clarifying the ecological background resources in the Yangtze River Delta region. Subsequently, an evaluation index system for the importance of ecological protection was constructed. Finally, ecological service functions and ecological sensitivity analysis results were obtained, and ecological areas with important conservation significance were identified. The research results show that the total area of the most important ecological protection areas in the Yangtze River Delta is 39170.30 km(2), accounting for 18.17%, which are mainly distributed in the southeastern and central and western parts of the Yangtze River Delta. The total area of important ecological protection areas is 94,606.54 km(2), accounting for 43.88%, and they are mainly distributed in the southern part of the Yangtze River Delta. The research results can provide a scientific basis for optimizing the ecological protection red line in the Yangtze River Delta region, carrying out zoning and classification of ecological protection, and constructing a green ecological environmental protection barrier.