Abstract: According to The Construction and Management Temporary Provisions of Mine Emergent Refuge System, a study was conducted on the power supply sy stem of the mine permanent refuge chamber in Wulan Mine .A double power supply system was designed and thus the mine electric power and the electric power in surf ace borehole could be automatically switched within five seconds.With the analysis on the gas explosion disasters occurred in the underground mine, the protection me asures of the underground electric cables with a buried depth of 500 mm were provided.Based on the power of the equipment in the chamber clarified, the voltage lost 0 f the cable should be calculated and the distance between the surface cable and the underground cable to the refuge chamber should not be over 1 500 m.Meanwhile, a plan of the surface borehole and the inner casing pipe layout was provided and the down setting method and fixed method of the cable in the borehole were determin ed.The safety power supply of the chamber site confirmed the feasibility of the power supply system.