Abstract: Objective As a sub-basin of the Tarim Basin, the Southwest Tarim depression was in the eastern part of the Paleo-Tethys Ocean during the Late Cretaceous, and it was affected by multiple transgressions and regressions cycles,then deposited thick marine evaporite formations, which indicates a good potential for potassium formation. Saline springs gushing out along the tectonic fissures are good carriers for indicating potassium-forming information in underground evaporites, among which the salt springs in the Wupa area are the most representative ones. However, the origin, transportation and enrichment process of salt springs in the Wupa area have not been thoroughly studied yet. MethodsThis study comprehensively analyzes the hydrochemical characteristics and hydrogen, oxygen, and strontium isotopes of 11 saline spring samples and 12 salt rust samples in the Wupa area to explore the source of recharge, migration mode, and evolution patterns. ResultsThe chemical composition analysis of the samples shows that the main hydrochemical types are chloride type and sulfate type, and the solute source is mainly from salt rock dissolving, and part of it comes from the leaching of carbonate minerals containing Ca. The overall K⁺ content of the samples is relatively high, indicating that the deep strata consist of potassium-rich rock layers. The ⁸⁷Sr/⁸⁶Sr ratio of the salt spring water shows that the salt layer is a marine salt layer. Conclusions The saline spring water in Wupa originates from atmospheric precipitation, which infiltrates downward through structural fractures, leaches the highly concentrated marine salt rock layers buried 194–566 meters underground, then flows upward through the fractures to emerge at the surface, and subsequently flows along gullies, gradually increasing in concentration and precipitating a large amount of salt frost. Combined with the discovery of potassium salt minerals, it is judged that the deep strata in the Wupa area are potassium-rich rock layers, possessing the potassium-forming elements of "abundant material sources-structural Closure-arid climate", and it is one of the most promising potassium-forming areas in the Southwest Tarim Depression. This study has important reference significance for the evolution of salt spring water in salt basins both domestically and internationally, and provides critical information for future potassium salt exploration in the region.