Abstract: In order to gain insight into the hydrochemical characteristics and formation mechanism of high fluoride groundwater in Zhuanlongwan Coal Mine, we conducted a comprehensive analysis of 48 samples including quaternary groundwater (QGW), sandstone groundwater (SGW), and mine water (MGW) using statistical analysis and hydrochemical methods. The findings demonstrate that the groundwater in Zhuanlongwan Coal Mine generally exhibits weak alkalinity, with predominant cations comprising of Ca²⁺ and Na⁺, and anions consisting of HCO₃^– and Cl^–. The mean mass concentration of SO₄ ^2–, Cl^–, TDS, pH, and CO₃ ^2– in groundwater follows the order of MGW>SGW>QGW, whereas HCO₃^– and F^– exhibit the trend of SGW>MGW>QGW. Specifically, the average mass concentration of F^– in QGW, SGW, and MGW is 0.76 mg/L, 4.55 mg/L, and 4.35 mg/L, respectively. Notably, most samples from SGW and MGW significantly exceed the permissible F⁻concentration threshold of 1.0 mg/L. The hydrochemical type of low fluoride (\rho_\mathrmF^- <1 mg/L) groundwater is primarily identified as HCO₃−Ca·Mg, whereas, the hydrochemical types of high fluoride groundwater (\rho_\mathrmF^- >1 mg/L) are mainly HCO₃−Na (35.42%) and SO₄·Cl−Na (45.83%). The dissolution of fluorinated minerals serves as the main source of F^– in the high fluoride groundwater of Zhuanlongwan Coal Mine. Moreover, cation exchange, competitive adsorption, as well as the dissolution and precipitation of dolomite and calcite, are significant factors influencing the occurrence of high fluoride groundwater.