Self-ignition of coal seam not only brings damage to coal resources and water resources, forest fires, environmental pollution, but also directly causes serious consequences of casualties. In order to rationally control the coal seam according to different conditions, based on the analysis of the spontaneous combustion cause and fire extinguishing mechanism of the coal seam in the Jurassic coalfield in northern Shaanxi, the use of flame retardant slurry grouting to form a curtain was proposed to isolate the fire source and inject cement powder into the curtain. The treatment method of coal ash slurry filling and strengthening the fire cavity of coal seam was given. Through the example of fire extinguishing engineering, the treatment effect of curtain grouting fire extinguishing was examined. The results showed that the curtain grouting fire extinguishing technology could realize the local treatment of the coal seam in the fire, which could be used as reference for the local emergency treatment of the coal field fire area.