Rainwater resources play a vital role in water resources balance, particularly in water-scarce regions. Regulating rainwater resources can help mitigate water supply-demand seasonal mismatch and support sustainable revegetation. However, the influence of revegetation on the rainwater resources use potential (RWUP)-comprising effective soil moisture and surface runoff-through land-atmosphere feedbacks remains uncertain. Here, we quantify the variations in the mismatch between water supply and demand as represented by precipitation (P) and the climatically appropriate for existing conditions P () in the Loess Plateau from 1999 to 2018. We examine the spatiotemporal patterns of RWUP by employing a coupled land-atmosphere model with scenario experiments, and reveal the mechanisms through which revegetation influences water resources balance. We quantify the maximum vegetation carrying capacity (MVC) under optimal RWUP regulation. Our findings show that revegetation could increase both P and , but exacerbate the seasonal mismatch between them. Effective soil moisture contributes 90% of the increase in RWUP, while surface runoff contributes 10%. The water resources balance is only marginally impacted by revegetation, as the increased RWUP, primarily from grass and crop, compensates for 86% of the increased evapotranspiration. Water-energy exchange induced by revegetation generate feedback effects on the local atmosphere, leading to increases in both P and RWUP. Regulating RWUP can enhance MVC (15%), supporting sustainable revegetation. Our results improve the understanding of the ecohydrological effects of revegetation from a water resources perspective, and highlight the critical role of RWUP in sustaining revegetation.