Abstract: Based on the occurrence features of close-distance seam and practical situation of mine production technology,through the in-depth study on mechanism and application characteristics of preventive grouting technology,the pre-grouting is done in the gob of No.Ⅱ₂ coal seam which is shallow buried,nonflammability,fire happened during mining process,and close to the first working face in No.3 coal seam of Ruqigou coal mine.The practice shows that the CO concentration in bubbing of the floating coal spontaneous combustion has remained at less than 10×10^-6 after pre-grouting in No.Ⅱ₂ coal seam gob,and no other representative gas is created at the same time,which ensures the safe recovery of the No.3 coal seam working face.This technology has obvious application effect for fire prevention and extinguishing in close-distance seams,can effectively prevent the occurrence and development of the recrudescence of existing fire zone and coal seam spontaneous combustion,and has strong practical significance for the protection of coal mine safety production.