Abstract: Aiming at the problem of gas extraction difficulties in single low-permeability coal seam,the method of using hydraulic fracturing technology to fracture coal seams and increase permeability is proposed,which can improve the effects of gas extraction.Taking 33071 drainage roadway in Hebi Zhongtai mining industry as the test point,through investigating parameters changing situations of drilling gas flow,gas extraction concentration and drainage flow before and after fracturing in hectometer boreholes,the results show that gas flow in hectometer boreholes is improved from 1.80 to 2.68 times;single-hole extraction concentration and flow are increased 7.5 times and 95 times respectively;seam permeability coefficient is increased by 9 to 18 times,while the attenuation coefficient is decreased from 210% to 280%.