Forests play an important role in removing greenhouse gases and in contributing to reduce global climate change, thus biomass estimation needed for forest management. This study performed remote sensing application using SPOT imagery to determine mangrove species distribution in Dat Mui Commune, Ngoc Hien district, Ca Mau province with 4 types of mangrove forests including Rhizophora forest, Avicenia forest, mixed-forest and fishery combined Rhizophora forest with the accuracy of 94.72%. Total forest area is 7.388,29 hectares which in Rhizophora forest and shrimp farming occupied the highest area of ​​4632.84 hectares at 46.8% of total area. Fresh biomass forest of each forest species were determined based on the age and different diameters level. The total fresh biomass forest is approximatelly 1450.71 tonnes and carbon storage was estimated around 2659.87 tonnes.