The position of the Hadley circulation edge (HCE) determines subtropical arid regions' locations, and its variations have attracted considerable attention. This research examines the effects of the preceding winter ENSO on the boreal spring northern HCE (NHCE) by influencing the spring tropical Indian Ocean (TIO) sea surface temperature (SST). The results of six reanalysis datasets show that El Nino and La Nina events have asymmetrical influences on the NHCE, as El Nino events are significantly associated with the equatorward shift of the NHCE. Specifically, when El Nino events occur in the preceding winter, the TIO SST warms in spring, with anomalous eddy momentum flux divergence (EMFD) gradients in the upper troposphere of the Northern Hemisphere, which cause the convergence center to shift equatorward. Additionally, the TIO warming increases subtropical temperatures, reducing the meridional temperature gradient (MTG) between the subtropics and tropics, and increasing the vertical wind shear and static stability, thereby enhancing baroclinic instability criterion (BIC) in the subtropical region and causing the NHCE to shift equatorward. However, when a La Nina event occurs in the preceding winter, the TIO SST cools during spring, but its weak impact on the EMFD, MTG and BIC contributes little to NHCE changes. Furthermore, by using ridge regression to compare the relative importance of the three relevant factors, it is found that variations in MTG and BIC dominate shifts in the NHCE latitude, while EMFD contributes less. This research enhances the understanding of the mechanisms driving HC changes during boreal spring and the atmospheric dynamics linked to these changes.