Abstract: Affected by Carbon Monoxide derived from goaf of working seam and adjacent layer, and various air leakage fault fissure communication channel, Carbon Monoxide Source is complicated and fire prevention is difficult during the retreatment of full-mechanized caving mining face. Aiming at the above existed fire-fighting technology problems during the retreatment at I011401 working face in Tunbao Coal Mine, through analysis and demonstration, technical measures were taken such as continuous nitrogen injection, three-phase foam grouting, backfill ground leak and mined-out area of adjacent layer airtight processing, mining work face protective sealing, etc. Based on these measures, good effect was achieved.