Abstract: In this paper,the divergent wind in the tropics is estimated by transforming satellite-observed OLR data to a velocity potential field.Then it is compared with that obtained from EC data.The difference in the velocity potential along the equator between two data sets is pronounced The diagnostic analysis indicates that the evolution of kinetre energy is close to objective development if the OLR data are considered in the divergenr wind field.Therefore it is possible to constitute a more precise wind field in the tropics by transforming OLR data to divergene and using the conventional data with suitable measures.These results ara helpful to the diagnostic analyses and the assimilation scheme in the tropics.