The invention relates to a drilling-explosion-pumping triadic gas extraction method, which is most suitable for regional gas extraction of a high gas and low permeability coal seam. The method comprises the following steps: alternately arranging hole positions of drainage holes and blast holes of an along bed or a cross seam on a coal seam in front of a coal mining or tunneling working surface; and performing construction work on the drainage holes one by one, and performing blasting operation, wherein through the edgetone effect of denotation gas in the blast holes, a columnar compression crushing circle and a crack body which passes through and blasts in the direction of a line of centers of the blast holes and the extraction holes are generated on the periphery of a blasting hole to transfer the ground stress, improve the gas permeability of a coal body, relieve the pressure in a coal body and facilitate for drainage of gas in the coal body. The gas permeability of the coal body can be improve by around 20 to 50 times, the gas extraction quantity of haplopore can be increased by 5 to 10 times averagely, the gas extraction concentration is more than or equal to 50 percent, and the gas extraction rate of a robbing working surface is more than or equal to 80 percent. After pressure releasing and permeability improving of drilling, explosion and pumping, the gas pre-extraction time can be shortened by half, and the number of drilling holes of gas extraction is decreased by 20 to 30 percent; and the method achieves safe, high-efficiency and uniform extraction of the gas in the high gas and low permeability outburst coal seam.