Abstract: By using a simple 3-layer primitive equation model, the responses of the low-level cross-equatorial flows to the heating field have been studied. The results show that the differential heating over the equatorial area has a great influence on both the position and the intensity of the cross-equatorial flows. The position of cross-equatorial flow coinsides with that of the heating gradient maximun. The changes of heating difference can lead to the variation of the cross-equatorial flows in their position and intensity. The effects of the heating field on the cross-equatorial flows may be realized by the variation of the divergent part of wind due to the effect of differential heating.The results of numerical experiments are quite similar to the observational aspects.