Abstract: In order to detect suspected fire zone at 8107 working face of Tashan Coal Mine in overlying Jurassic ancient kiln gob, isotopic radon measurement method was used to detect the fire zone and quantitatively analyze its evolution trend. Meanwhile, industrial television drilling analysis was used to qualitatively analyze the possibility of fire incursion. Additionally, a series of fire prevention technology was prepared, which guaranteed safely mining of 8107 workface.