The present project was intended to study marine biological diversity in coastal zones of Viet Nam, its modern status, threats, and recent and modifications due to global change and human impact. A synthesis of data and original research were conducted on coral reef modifications, biota of the intertidal zone, meiobenthic communities, species richness of rare groups of animals and economically important molluscs and the results of this synthesis and research are presented. There are numerous threats to marine biodiversity in the coastal zones of Viet Nam: habitat degradation, fragmentation and loss; global climate change including sea level rise, storm events, rainfall pattern change, warming of the coastal ocean; effects of fishing and other forms of overexploitation; pollution and marine litter; species introduction/invasion; physical alterations of coasts; and tourism. The data of Vietnamese and Russian researchers on biodiversity and coastal zone management was consolidated and used to interpret ecosystem changes and develop recommendations for local/national decision makers. The project’s outcomes are not only relevant to coastal zones of Viet Nam, but may also contribute to current understanding of the entire ecosystem of the South China Sea.