Abstract: During the mining process in three-level main haulage roadway in a certain mine, the close distance coal seam groups of A3-1, A3-2 and A5 with gas accumulation leading to the increase of danger coefficient in the tunneling of coal seam. We implement drilling prediction in the process of exposing A2 coal seam and the rock section of drilling appears hole-spray phenomenon; we analyze related hole-spray with the aid of the gas field monitoring and geological data, and propose the pre-drainage of implementing three-layer close coal seam by concentrating drainage holes, and draw the following conclusions that the gas emission near coal line and carbonaceous mudstone metamorphic causes the hole-spay of rock section; in exposing very thin coal, coal gangue mixed line, we determine gas desorption index of drill cuttings K₁ value as the standard, in the judgment of outburst dangerous, taking daily critical value of 70% to 80% as the threshold; before uncovering coal, we should implement centralized layout of drainage borehole in advance, the gas concentration pre-drainage of A3-2, A3-1, A5 coal seams can reduce the quantity of rock cross-cut coal uncovering and risk coefficient.