A study of the zoobcnthos in the coastal mangrove ecosystem of North Central Vietnam was carried out in May 2013. The result has recorded 168 species and subspecies belonging to 49 families, 93 genera and 3 classes (Crustacea, Gastropoda and Bivalvia). Crustacea is most abundant in terms of number of species (41.6 percent), while for Gastropoda it is 33.4 percent and for Bivalvia it is 25 percent. Most of the species recorded in this areas are widely distributed in Vietnamese mangrove forests and on coastal areas on the western shore of the Pacific Ocean. It was also found that more species live in the mangrove forests of Thanh Hoa and Thua Thien Hue provinces than in Nghe An, Ha Tinh, Quang Binh and Quang Tri provinces. The population density of Gastropoda is greater outside mangrove forests than inside mangrove forests while for Crustaceans and Bivalves, the population density is greater inside mangrove forests than outside mangroves forests.