Based on the occurrence characteristics of the soft, fractured, and thick large orebodies in a gold mine, the mechanized upward drift filling mining method was recommended. Six sets of stope structural parameters were designed through an orthogonal experiment, and the FLAC3D numerical simulation software was utilized to analyse the stope stability. The simulation results indicate that the compressive and tensile stresses in the stope are mainly concentrated at the top and bottom corners of the sidewalls, and both exhibit a symmetrical distribution. The displacement values of the stope roof, floor, and hanging wall surrounding rock increase with the increase of the drift width and drift height, but the overall displacement values are relatively small. On the premise of ensuring the safety and stability of the stope, larger stope structural parameters are preferentially selected to improve the technical and economic indicators. Therefore, Scheme 3 (with both the drift width and drift height being 5 m) is determined as the optimal stope layout scheme. The field application results indicate that when the mechanized upward drift filling mining method is adopted for extraction, the stope production capacity reaches 220 t/d, and the development and cutting ratio is 24.5 m³/kt. Furthermore, the ore loss rate is 6.2%, and the dilution rate is 8.3%, achieving favourable technical and economic benefits.