Abstract: Using NOAA polar-orbiting meteorological satellite data, the distribution and the changes of the underlying surface reflectance, vegetation index, underlying surface temperature and outgoing longwave radiation (OLR) are studied under the condition of cloud-free in both dry and wet seasons in Hainan Island. It is proved that the application of satellite data is highly effective to the study of underlying surface regime, which is one of the important factors for the local climate.