With the acceleration of urbanization and the rapid development of urban and rural construction, environmental problems have emerged, which are specifically manifested in the fragmentation of semi-natural habitat patches on the outskirts of cities, the degradation of ecosystem service functions of green areas, and the disintegration of blue-green spaces. Influenced by factors such as the properties of ecological transition zones and blind zones of composite spatial governance, the urban periphery has become a centralized carrier of human-land system conflicts and a key spatial interface for conflict resolution. Focusing on biodiversity conservation in blue-green areas around cities, this study explores the theory and current status of related research at home and abroad. The aim is to provide useful references for future research and practice in this field, and to provide methodological knowledge and practical suggestions for biodiversity conservation in blue-green areas around cities.