Abstract: In this paper, a numerical experiment is made by means of the two-dimensional zonal average model in order to study the influence of the changes of sea-surface temperature(SST) upon the seasonal movement of subtropical high. The results show that there exists a lag-time about three to five months in the seasonal movement of subtropical high subject to SST of the middle latitude. So that when the flux of sensible heat on the western pacific ocean surface in the middle latitudes is positive departure, the subtropical high will be weakened and pushed southward, and vice versa.