Abstract: The article analyzes the applicability of current common fire source detection technology. Aiming at the characteristics of shallow buried and the ground without vegetation in small coal mine fire area around Yujialiang Coal Mine. The study chose technology of isotopic radon measurement to detect fire. It took drilling grouting, compaction with covered loess, building buffer zone and a blocking firewall and other measures for the abnormal area. The small coal mine fire area has been effectively controlled. It verified the accuracy of isotopic radon measuring method in detecting hot spots in the fire area, and eliminating the small coal mine fire zone threat to safety production of Yujialiang Coal Mine.