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The coal-gas existing condition was ameliorated in the coal seams prone to coal-gas outburst adopting the mining method of protective strata. The gas volume and the gas pressure were reduced synchronously in the protected coal seam, and the coal seam of high permeability prone to the coal-gas outburst was changed into that of low perme-ability with no proneness to the coal-gas outburst. The D15 coal seam was treated as the protective strata, and the D16-17 coal seam was treated as the protected strata in the Fifth coal mine in the Pingdingshan Coal Mining Group. The distance between the two coal seams was 5 m averagely, clarified into the extreme short-range protective strata. The numerical analysis was based on the theory of the porous media flow with the finite ele-ment method. The gas flow process and the change mechanism of the coal-gas pressure were analyzed in the process of mining the protective strata.