Abstract: In order to solve the problem of inefficiency of gas drainage, too long gas drainage time affecting production supersede in a single hard outburst coal seam, in the laboratory, the crack cut-through length is increased by hard coal seam by blasting through strata; the similar simulation experiment was carried out to improve the permeability of coal seam. By experiment, for borehole blasting, cracks formed by explosion in hard coal seam were longer and had better connectivity. Through analysis, blasting stress wave propagation in the hard coal seam can not easily be absorbed. The stress wave propagation to the harder rock will produce the reflected wave, continuing to react upon coal seam to continually promote expansion of the fractures, so that the coal seam cracks will be extended and penetrated. Finally, the application of deep-hole blasting through strata was taken in Ⅱ₁ coal seam of Zhaogu No.2 Coal Mine. The research result shows that gas drainage density enlarges 81.18% to 91.79% compared with gas extration data before blasting, the pure amount of gas draining enlarges 3.50 to 6.07 times.