Abstract: The identification of the ecological source of the county and the construction of ecological security pattern are of great significance to the ecological protection of the Three Gorges reservoir area. Taking the county-level Jiangjin District of the Three Gorges reservoir area as an example, based on the improved minimum cumulative resistance (MCR) model and GIS spatial analysis techniques, the minimum cumulative resistance surface for ecological source expansion and the minimum cumulative resistance surface for construction land expansion are constructed to identify ecological corridors, radiation pathways, ecological strategic nodes and other ecological processes, then build an ecological security pattern. The results showed that 10 expansion resistance factors and 9 urban land expansion resistance factors were determined; the low-level ecological security pattern in Jiangjin District was 994.71 km2, accounting for 30.98% of the total area of Jiangjin District; the high- level ecological security pattern only accounted for 23.66% of the total area of Jiangjin District; 38 ecological corridors and 14 ecological strategic nodes were identified; different level ecological safety grids can be used as a basis for ecological protection and development in the Three Gorges reservoir area.