In the context of rapid urbanization and land space planning, assessing regional ecosystem services and constructing ecological security patterns are effective methods to the urban smart protection and growth. Based on the supply efficiency of ecosystem services and muti-source data, this study took Yangtze River Delta Ecological Greening Development Demonstration Area as an example to classify a comprehensive evaluation system of water-land coupling ecosystem services into two aspects of aquatic and terrestrial. After that, we identified high supply areas as the ecological source areas, extracted corridors and nodes based on minimum cumulative resistance model and circuit theory for the regionally ecological security pattern. This paper obtained the following results:1) 34.31 km² and 272.5 0km² of land and water habitat patches were identified, respectively, which provided a theoretical basis for the spatial survival of Jiangnan waterside areas and the spatial selection of urban green space. 2) Forty-one sources were evaluated by water-land coupling degree with a total area of 206.79 km², accounting for 8.57% of the study area, whose pattern appeared as "more in the northwest than the southeast". 3) A total of 89 ecological corridors and 91 ecological nodes were extracted. The corridors had a total length of 586.35 km and a uniform network distribution, and the nodes included 44 pinch-points and 47 barriers, mainly located in Wujiang District. Through the construction and priority evaluation of the regionally ecological security pattern, the study offered suggestions for ecological protection and restoration proposed in a hierarchical manner, providing references for the rational layout of ecological space, transformation and management of land use in other rapidly urbanized areas and regions around metropolises in China.