Abstract: To investigate the mechanisms by which coal mining affects overburden aquifers, this study takes the Zhundong Dajing No.2 Mine as a case study and integrates theoretical analysis with numerical simulations to elucidate the evolution of mining-induced stress in the overburden, the spatiotemporal variation of aquifer permeability, and the coupled responses of groundwater level and flow field under high-intensity mining. The results indicate that, after coal mining, an arch-shaped pressure-relief zone develops above the goaf and expands continuously with face advance; stress concentration on both sides promotes the upward propagation of water-conducting fractures, and the degree of stress release attenuates progressively with increasing height above the roof. Overburden failure and aquifer connectivity exhibit clear stage characteristics: when the face advances to 100 m, 300 m, and 500 m, the maximum height of the plastic zone reaches approximately 47 m, 295 m, and the ground surface, respectively, successively connecting the Xishanyao Formation and Shishugou Group aquifers and then impacting the Tugulu Group aquifer. Monitoring further shows that the roof fracture height is about 258 m at an advance of 270 m, in good agreement with the simulated development height of the plastic zone. Under mining disturbance, the permeability coefficient demonstrates pronounced spatial heterogeneity: above the goaf it follows a “high in the middle and low at both ends” pattern, mainly controlled by the coupled effects of rock mass compaction and dynamic stress-field adjustment, whereas away from the goaf it presents a “low in the middle and high at both ends” pattern, reflecting delayed deep energy dissipation and cumulative damage. The groundwater model achieves a good water balance （recharge 8 445.71 m³/d, discharge 8 445.91 m³/d, relative error 0.002 4%）, and the relative error of inflow verification is less than 5%. The overall groundwater flow direction in the study area remains from north to south; however, the local flow field above the goaf is reshaped and a drawdown cone centered on the goaf forms. With continued face advance, the cone expands, the central water level declines, and both the hydraulic gradient and groundwater flow velocity increase. Aquifer responses exhibit distinct spatiotemporal differences: near-field aquifers respond earlier and more strongly, whereas far-field aquifers show weaker responses, with limited drawdown and cone expansion due to the delayed development of water-conducting fractures. These findings provide a basis for inflow prediction and zoned prevention and control of mine water hazards.