Mangrove forest has various functions, such as wind and wave prevention, embankment protection, biodiversity and ecological balance maintenance, which is with high value in the ecological, social and economic. Hainan is the region where the type of Mangrove forest is most abundant, its area is biggest, its growth vigor is best. Hainan mangrove forest is very important to the ecological, scientific research and tourism. Hainan International Tourism Island Construction, which had been proved by state council, will bring great influence on the quality and range of Hainan mangrove forest. It is with positive guiding significance to the changing monitoring of mangrove forest and projection measures making to obtain the distribution information of Hainan mangrove forest and other land cover types, compare and analysis the area changing of all kind of land cover types based on Remote Sensing and Geographic Information System.