Ecological corridors have the function of maintaining or restoring ecological connectivity, and are important for connecting the biological habitats and protecting species diversity. Existing studies on ecological corridors have mainly focused on land, while marine ecosystems are characterised by extensive water connectivity and lack of visual landscape patches, making the study of marine ecological corridors a long-standing scientific challenge. In this study, the Indo-Pacific humpback dolphin (Sousa chinensis), a national level protected species in Xiamen Bay, was used as the target, and a method for identifying marine ecological corridors was developed based on the species distribution model and the least-cost path analysis. The study used a species distribution model to identify suitable habitat areas and nodes for Indo-Pacific humpback dolphins in the Xiamen Bay, and used the habitat suitability results of the model to generate a resistance surface in the ocean and simulate the least-cost path between nodes and nodes on the resistance surface, so as to generate a species dispersal network. The results showed that the distribution of Indo-Pacific humpback dolphins in Xiamen Bay was mainly influenced by three factors:channel distance, distance to shoreline, and chlorophyll concentration, while the main suitable habitats were located in the western waters to the mouth of Jiulong River and Dadeng waters. The potential core ecological corridor covered an area of 93.19 km² and the secondary ecological corridor covered an area of 170.41 km². The route along Jiulong River Estuary-south of Gulangyu Islet-Huangcuo-Dadeng Island and Xiaodeng Island may be the main migration route of Indo-Pacific humpback dolphins in Xiamen Bay. On this basis, the assessment of the disturbance of human activities on the corridor was carried out in terms of the overlapping of sea-use space and the impact of bridges. The assessment results indicate that tourism and shipping activities are likely to be the main sources of impacts on the Indo-Pacific humpback dolphin ecological corridor, with the core corridor being more influenced by tourism activities and the secondary corridor being more influenced by shipping activities. In addition, the bridges in the northern part of Xiamen Island may also affect the connectivity of the Indo-Pacific humpback dolphin ecological corridor. This study innovatively proposes a spatially quantified identification method for marine ecological corridors and successfully applies it to the study of the Indo-Pacific humpback dolphin in Xiamen Bay. The results of this study can provide new scientific tools for the conservation of marine biodiversity and the spatial planning of marine protected areas in China.