Based on large gas emission and broad gas distribution of thick coal seam fully mechanized working face of Tunliu Mine, numerical simulation was adopted to study thick coal seam fracture development scope, the double roadway after mining, the working face transportation roadway was used as the gas drainage roadway of the working face, the high drilling was set and goaf drainage and screen comprehensive method was adopted, the gas released to goaf in mining was drained. The study showed that high drilling should extend to the central working face goaf upper 28 m, after the drainage, the average gas drainage by high drilling achieved by 20.18％, average screen drainage by 19.1％, which effectively controlled goaf gas emission to working face and the upper corner gas concentration.