Abstract: The Tielieke fluorite deposit is located approximately 60 km northwest of Baicheng County, Xinjiang, and tectonically belongs to the South Tianshan orogenic belt. To date, more than 20 ore bodies of varying sizes have been discovered and are widely distributed. They occur within the limestone of the Upper Carboniferous Kalazhierjia Formation and are jointly controlled by NW and NNW-trending joints, karst vugs in carbonate rocks, and interlayer fractures. The ores are mainly composed of green, purple, and white fluorite with brecciated and massive structures, and contain abundant calcite and quartz. The fluorite is predominantly euhedral to subhedral in texture. Based on field work and ore paragenetic relationships, three mineralization stages can be distinguished: the green fluorite-quartz-calcite (minor) stage (Ⅰ), the white fluorite-purple fluorite (minor)-quartz-calcite (minor) stage (Ⅱ), and the calcite stage (Ⅲ). In order to understand the nature and source of the ore-forming fluids, the source of ore-forming materials, and the genesis of the Tielieke fluorite deposit, this study carried out fluid inclusion microthermometry, C-H-O isotope and rare earth element (REE) analyses. The results show that: ①The fluid inclusions are mainly gas‐liquid two-phase inclusions. The homogenization temperatures range from 88.3 to 199.9°C, and the salinities range from 0.2 to 12.6 wt% NaCl eq., indicating a low-temperature, low-to-moderate salinity NaCl-H₂O system. ②The δD values of the ore-forming fluids range from −146.5‰ to −131.6‰, and the δ¹⁸O_H2O values range from −5.97‰ to 5.33‰. On the δD-δ¹⁸O diagram, the data points plot between the meteoric water line and the field of Carlin-type gold deposits, indicating that the fluids are predominantly circulated meteoric water that underwent water-rock interaction with the rocks they passed through. The δ¹³C values of hydrothermal calcite range from −1.08‰ to 0.37‰, which are similar to those of the host limestone (0.05‰ to 1.16‰), suggesting that the carbon was mainly derived from the dissolution of the host carbonate rocks. ③The REE distribution patterns and variations in Sm/Nd ratios reveal that part of the Ca in the ore-forming materials was derived from the host rocks. Both fluorite and calcite exhibit significant negative Eu anomalies (0.13–0.44) and negative Ce anomalies (0.50–0.85), indicating that the ore-forming fluid was characterized by high oxygen fugacity overall. The LREE/HREE vs. REE diagram and the La/Ho vs. Y/Ho diagram indicate that the three mineralization stages did not evolve continuously but rather resulted from the superposition of three fluid pulses, accompanied by recrystallization. ④ The Tb/La vs. Tb/Ca diagram and the Yb/La vs. Yb/Ca diagram indicate that both fluorite and calcite are of hydrothermal origin with a relatively high degree of water-rock interaction. In summary, the Tielieke fluorite deposit is interpreted as a low-to-moderate temperature stratabound hydrothermal deposit, with fluorite precipitated in joints and fractures.