In view of the problems such as shallow borehole depth, low rates in borehole completion, presence of blind drainage areas in the broken-soft coal seam, it was proposed to use the comb type directional boreholes in the floor for long-distance and regional gas drainage and control in light of the occurrence characteristics of the coal seam, its roof and floor strata in Qinglong Coal Mine, Guizhou Province. Firstly, the construction principle and technical advantages of the comb directional boreholes on the floor were analyzed, and the design principles of the comb directional borehole on the floor were summarized from the selection of borehole target layers, kick-off point and borehole spacing. Through the optimization of drilling equipment, drilling technical parameters and drilling tool combinations, the fractured coal seam and rock along the borehole were drilled through successfully, and the 127mm casing protection boreholes were run in the hole. Several comb directional boreholes were completed in the floor at No. 21605 bottom drainage roadway. The gas drainage effect shows that the gas drainage flow rate is large, the concentration is high, the attenuation rate is slow, the single borehole drainage concentration is 60%～85%, the drainage purity is 0 .8 to 1.5m3/min, achieving high-efficiency gas drainage. The study provides an important reference for regional gas drainage and control in the broken-soft coal seam.