Abstract: Plastic pollution has become a global environmental problem, especially in the estuary-offshore ecotone. Damaged and discarded fishing gear in aquaculture activities has become one of the main direct sources of plastic pollution. In recent years, China has carried out investigations and research on plastic pollution in typical estuaries, bays and tidal flats of key sea areas, and accumulated scientific data and research foundation. However, multiple aspects such as methodology, pollution assessment and supervision technology still fall short of meeting the environmental pollution control requirements of abandoned fishing gear. This paper systematically reviewed the use of plastic fishing gear in aquaculture and the pollution caused by it, analyzed the threats to the environment and ecology of land-sea ecotone, and discussed the management measures and concepts of sustainable development for abandoned fishing gear. The aim was to form a synergistic management system for monitoring and controlling plastic pollution in estuary-offshore ecosystems. The research can provide policy support for the environmental security of the offshore ecotone and a theoretical reference for the formulation of comprehensive management strategies coordinating land and marine ecosystems.