The coastal ocean, which offers substantial support and important space for the sustainable development of human society, is subject to multiple stressors including anthropogenic activities and climate changes, and the potential consequences of growing human pressures on marine ecosystems attract much attention.In line with the recognition on structures, functions, and services of coastal ecosystems, as well as the significant changes of coastal ecosystems recently occurred under multiple depressors, issues on the health of coastal ecosystems and ecological security became hot spots in marine studies.The knowledge on ecological security of coastal ecosystems, however, is still quite limited, and hampered by the lack of methodologies on coastal ecosystem assessment.It is suggested to develop capabilities on long-term observation and information collection concerning marine ecosystems, and to perform assessment on the status of coastal ecosystems, which will offer sound basis for the implementation of marine ecosystem-based management.