The microplankton phytoplankton community in the coastal community of Trang found in the Tropical Oyster culture area consists of 38 phytoplankton species that can be classified to the genus level, with the Class Bacillariophyceae group. It is the group with the highest composition of 30 genus, followed by Class Dinophyceae with 5 genus, Class Cynaophyceae with 2 genus, and Class Dictyochophyceae with 1 genus.