Abstract: To solve the problem of the gas consistence exceeding limit at the upper corner of working face. The distribution law and charicteristis of overburden strata “three zones” during mining are studied by physical simulation experiment aim at the situaton of (4-5)04 working face in Liu Huanggou Coal Mine. High level borehole is designed by the experiment result for drainage gas in upper corner of working face and its drainage effect is observed and analyzed in real time. The results shown that caving degree is about 71°and there are a lot of fracture in overburden strata. The height of caving zone and fractured zone are 25~26.8m and 109.2~110m. Its first weighting interval and average periodic weighting distance is 36m and 16.6m. The width of cracked is 40m near cut hole. It is about 30m near reture airway and airflow airway. It is from 20m to 40m near working face during mining. Reasonable air supply of working face is 1100m3/min and drainage subpressure is 30~40kPa from the results of numerical simulation and field observation. It is 7.00~26.03% that the drainage concentration of high level borehole from the field observation. Average effective distance of borehole is 54.5m. The value of gas concentration of upper corner and working face are is controled under 0.27% and 0.32%. The working face is mined safely and effectively.