The South China Sea (SCS) is significantly influenced by El Nio and the Southern Oscillation (ENSO) through ENSO-driven atmospheric and oceanic changes.We analyzed measurements made from 1960 to 2004 to investigate the interannual variability of the latent and sensible heat fluxes over the SCS.Both the interannual variations of latent and sensible heat fluxes are closely related to ENSO events.The low-pass mean heat flux anomalies vary in a coherent manner with the low-pass mean Southern Oscillation Index (SOI).Time lags between the heat flux anomalies and the SST anomalies were also studied.We found that latent heat flux anomalies have a minimum value around January of the year following El Nio events.During and after the mature phase of El Nio,a change of atmospheric circulation alters the local SCS near-surface humidity and the monsoon winds.During the mature phase of El Nio,the wind speed decreases over the entire sea,and the air-sea specific humidity difference anomalies decreases in the northern SCS and increases in the southern SCS.Thus,a combined effect of wind speed anomalies and air-sea specific humidity difference anomalies results in the latent heat flux anomalies attaining minimum levels around January of the year following an El Nio year. The South China Sea (SCS) is significantly influenced by El Nio and the Southern Oscillation (ENSO) through ENSO-driven atmospheric and oceanic changes. We analyzed measurements made from 1960 to 2004 to investigate the interannual variability of the latent and sensible heat fluxes over the SCS.Both the interannual variations of latent and sensible heat fluxes are closely related to ENSO events. low-pass mean heat flux anomalies vary in a coherent manner with the low-pass mean Southern Oscillation Index (SOI). Time lags between the heat flux anomalies and the SST anomalies were also studied. We found that latent heat flux anomalies have a minimum value around January of the year following El Nio events. After and after the mature phase of El Nio, a change of atmospheric circulation alters the local SCS near-surface humidity and monsoon winds.During the mature phase of El Nio, the wind speed decreases over the entire sea, and the air-sea specific humidity difference anomali es decreases in the northern SCS and increases in the southern SCS.Thus, a combined effect of wind speed anomalies and air-sea specific humidity difference anomalies results in the latent heat flux anomalies attaining minimum levels around January of the year following an El Ni o year.