Salt-Overly-Sensitive (SOS) signaling module comprising the sodium-transport protein SOS1 and the regulatory proteins SOS2 and SOS3, is well known as the central salt excretion system that helps plants against salt accumulation. Here we report that VPS23A, a component of the endosomal sorting complex required for transport (ESCRT), plays an essential role in the function of the SOS module to confer plant salt tolerance. VPS23A enhances the interaction of the SOS2/SOS3 complex. In the presence of salt stress, VPS23A positively regulates the process of re-distribution of SOS2 to the plasma membrane and then activates the antiporter activity of SOS1 to reduce Na⁺ accumulation in plant cells. Genetic evidence demonstrated that salt tolerance achieved by the overexpression of SOS2 and SOS3 depended on VPS23A. Taken together, our results identified that VPS23A is a crucial regulator of the SOS module that affects the subcellular localization of SOS2 to the cell membrane. Moreover, the strong salt tolerance of Arabidopsis seedlings conferred by a membrane-bound SOS2 revealed the significance of the action of SOS2 sorting to the cell membrane in achieving its function.