Abstract: The ecosystem in the water towns of Jiangnan is facing threats in the process of high urbanization. Identifying key areas for ecological protection, restoration and protecting is important. This study selected Jintan district of Changzhou City as a typical case of the Jiangnan water town area. We used island biogeography theory to identify ecological sources. The ecological corridors were extracted based on the minimum cumulative resistance model (MCR). Combined with gravity model, the importance of the ecological corridors was graded. The regional ecological bottlenecks and obstacles were then identified. Based on these, an ecological security pattern was constructed to provide strategies for ecological restoration. The results showed that: (1) the area of regional ecological source was 152km2. There were 44 terrestrial ecological sources with a total area of 49.3 km2, which were concentrated in Maoshan; There were 77 ecological water sources with a total area of 102.7 km2, which were distributed in Changdang Lake. (2) The total length of ecological corridors was 432.4km, and the land ecological corridors were distributed in a "horizontal umbrella" pattern, while the water ecological corridors were distributed in a "double-loop" pattern. The extremely important ecological corridor was 93.2km, the important ecological corridor was 157.8km, and the generally important ecological corridor was 181.4km. (3) There were 16 ecological spots including 9 important ecological spots, which was mainly located in Maoshan and Tianhuang Lake in the west of Jintan District; There were 14 ecological obstacle points including 6 major ecological obstacle points, which were distributed in the main urban area of high building density and the intersection between high-grade roads and ecological corridors. (4) Based on the principles of effective connection of major habitat patches, protection of key pinch points and restoration of key obstacles, we proposed that a national spatial ecological security pattern of "one core, three areas, and five belts" be built in Jintan District. This study provided reference for carrying out land spatial ecological protection and restoration in the Jiangnan water towns in the lower reaches of the Yangtze River.