Located in Dongru Township, Ritu County, Ngari Prefecture, Xizang, the Jiezechaka Salt Lake contains substantial mineral resources, including 2. 3 million tons of LiCl, 1. 6 million tons of B2O3, and 9. 79 million tons of KCl. As one of the few lithium mines under development in Xizang, studying the material sources of the salt lake water and its recharge water holds significant scientific and practical importance. This paper systematically analyzes the hydrogeochemical characteristics of Jiezechaka Salt Lake and its recharge water sources. A total of 65 samples, comprising lake water, river water, and spring water were collected and analyzed for TDS, pH, and main ion composition. Using Chadha hydrochemical diagrams, Piper cation- anion ternary plots, and Gibbs diagrams, we investigated the main ion characteristics, controlling mechanisms, and material sources of the lake and recharge water. The results show that the salt lake water exhibit an Na- CO3 hydrochemical type, while river water is classified as Ca- Mg- HCO3 and Na- HCO3, and the hydrochemical type of spring water is Na- HCO3. The hydrochemical composition is mainly affected by rock weathering and evaporation- crystallization processes. In river and spring water, Na+ and K+ are mainly derived from evaporative karst decomposition such as rock salt, whereas Ca2+and Mg2+are mainly derived from the dissolution of silicate rock. Metallogenic elements such as Li, Rb and Cs are sourced from rock weathering and deep water- rock reactions. The annual recharge volumes of Hebian spring, Dongru Spring, and Qingshui River are 1601600, 6440900 and 93616500 m3, respectively, with river water accounting for 92. 09% of the total recharge. The annual replenishment of Li, Rb, and Cs in river water is about 3501. 26 kg, 176 kg and 156. 34 kg, respectively. The annual replenishment of Li, Rb and Cs in spring water is about 6824. 18 kg, 288. 87 kg and 691. 59 kg, respectively, representing 66%, 62% and 82% of the total recharge for these elements, respectively. The Chaka mud fields and membrane fields, covering an area of about 10. 40 km2, exhibit progressive enrichment of Rb and Cs in the brine following lithium and potassium extraction. This enrichment has reached concentrations sufficient for separate Rb and Cs mining, comparable to the industrial grade observed in Zabye Salt Lake. The water level of Jiezechaka Salt Lake has risen, and its area has expanded. By April 2023, the lake covered 118. 07 km2, making an increase of 12. 69 km2 since 1977. This expansion has implications for salt lake production, underscoring the need for continuous monitoring of lake water dynamics to assess long- term impacts.