Abstract: In order to clarify the water filling sources of the mine water in Bulianta Coal Mine and the replenishment ratios of each water source, so as to ensure the rational allocation and safe management of the mine water resources, hydrogen-oxygen stable isotope tracer analysis was carried out in this study. A total of 28 water samples were collected for the study, covering surface water, Quaternary diving, water from the Zhidan Group, water from the Yan’an Formation and water from the goaf. The δ¹⁸O and δ²H values were determined by wavelength scanning cavity ring-down spectroscopy (WS-CRDS) technology, and the contribution ratios of each water source to mine water were calculated by applying the IsoSource model. The results show that the aquifer water of the Yan’an Formation is the main water source of the mine, accounting for 50. 4%. The water in the goaf and the quaternary diving accounted for 25. 3% and 21. 0% respectively. The water of the Zhidan Group accounts for 2. 5%, while the contribution of surface water is only 0. 7%. The root mean square error (RMSE) calculated by the model is 0. 069, indicating a good fitting effect and high reliability of the results. Based on the results of isotope analysis, this paper proposes an optimization strategy for mine water resources management, covering measures such as water source monitoring and assessment, rational allocation, water quality treatment and pollution control, providing a strong scientific basis for the efficient utilization and protection of mine water resources.