Abstract: In order to study the influential factors of gas extraction effect during the nitrogen injection displacement process in ultra-high-pressure hydraulic slotting boreholes in coal seams, a numerical model of slotting boreholes was established, and a solid-gas coupling model for promoting CH₄ extraction from coal seams during the nitrogen injection process in slotting boreholes was constructed.The COMSOL Multiphysics software was used to simulate the gas extraction effect of slotting boreholes under different conditions.On the basis of demonstrating the effectiveness and advantages of the dual-enhanced extraction of slotting and nitrogen injection, a field industrial test was carried out.The results show that according to the numerical simulation, it is ideal to select a borehole spacing of 5 m for slotting boreholes, a gas extraction negative pressure of-20 kPa, and a gas injection pressure of 2 MPa.The field industrial test shows that the maximum pure gas extraction volume of the inspection boreholes in the slotting area and the slotting+nitrogen injection area increased by 160.12% and 348.12%,respectively.The gas extraction volume of the inspection boreholes in both areas increased significantly, and the influential radii of gas extraction in the hydraulic slotting area and the hydraulic slotting+nitrogen injection area both exceeded 10 m.