The black-and-white snub-nosed Monkey (Rhinopithecus bieti, BWSM), a critically endangered species in Southwest China, faces severe threats from habitat loss, fragmentation, and migration barriers. Establishing and maintaining ecological corridors is crucial for its conservation. This study utilized the current distribution range of the BWSM as ecological source areas and employed the Linkage Mapper tool combined with the gravity model to extract ecological corridors and nodes, classify corridor hierarchies, and assess resistance factors. The key findings include the following: (1) Twenty-eight ecological source patches were identified, showing an island-like distribution with protection gaps; (2) Migration resistance followed a spatial pattern of south > north > central; (3) Thirty-five ecological corridors were extracted, including 10 first-level, 19 second-level, and 6 third-level corridors, predominantly oriented north-south. Additionally, 45 barrier points and 41 pinch points were identified, both of which exhibited discrete distributions. First-level corridors presented no barriers, while barrier and pinch points accounted for 41.1% and 30.24% in second-level corridors, and 58.9% and 69.76% in third-level corridors, respectively; (4) Land cover, residential areas, and road networks were the primary resistance factors affecting ecological corridors, while water systems and elevation had minimal influence. Secondary and tertiary corridors face migration obstructions due to fragmented vegetation, extensive residential development, and dense road networks. These findings provide a scientific basis for prioritizing the restoration and construction of ecological corridors to enhance habitat connectivity for BWSM conservation.