Abstract: In view of goaf spontaneous combustion prevention of 12401 fully mechanized working face with large mining height in Shangwan Coal Mine, CO is determined as prediction index gas of coal spontaneous combustion and C2H4 is used as auxiliary index gas to master coal spontaneous combustion through temperature programmed oxidation experiment. Gas in goaf is monitored by laying beam tubes on air return side in goaf of the working face, and spontaneous combustion "three zones" in goaf were divided according to monitoring results. Heat dissipation zone is 0-32 m away from the working face, spontaneous combustion zone is 32-225 m away from the working face, and suffocation zone is 225 m away from the working face. According to total length of heat dissipation zone and spontaneous combustion zone and the minimum coal spontaneous combustion period, the minimum safe advancing speed of the working face is about 6.4 m/d. The research results can provide reliable basis for formulation of fire prevention measures on the working face.