Abstract: based on the surface meteorological and radiosonde data during the IOP of TOGA-COARE at observation station (2°15′S,158°E)of "R/V Shiyan3",the heat flux during IOP is exhaustively analysed,especially for the heat flux of two WWBs(westerly wind bursts) over the tropical western Paciffic during IOP.Meanwhile,the relationships among large-scale circulation middle and high latitude circulation have been discussed.The results show that the latent and sensible heat fluxes over the tropical western Pacific,which have been transported from sea surface into air,are maximum in both WWBs,their causes of formation have important relations with the cross-equatorial flow from winter hemisphere,and the transportation of heat is differient under different weather conditions.