Abstract: Based on the marine meteorological data collected by the vessel "Xiangyanghong No.14,China" and other ships from January through February, 1986,the heat balance of the sea surface in three areas in the western tropical Pacific has been estimated in this paper. It is shown that the net heat gained by the sea surface is negative. It means the supporting energy from the sea surface to the atmosphere is larger than the energy received from atmosphere by the sea surface. It should be emphasized that the area where the heat transport from sea surface toward air is most evident is the west part of the western tropical Pacific around 10°N. Additionally,the latent heat flux and solar radiation flux should be two of the most important factors in determining the sea surface heat balance in this region.