Abstract: In order to study the parameters for rational distribution of high level directional drilling in fully mechanized working face, taking the goaf of 12318 working face in Wangjialing Coal Mine as the research object, strata numerical model was established by using numerical simulation software. The distribution characteristics of overburden stress and fracture in goaf were analyzed, the distribution range of rock fracture zone in goaf was pointed out quantitatively, the rational distribution parameters of high level directional drilling were optimized, and the extraction effect of optimized high level directional drilling was investigated, the reliability of the analysis results was verified. The results show that the average gas extraction concentration is increased by 1.0 times, the average gas extraction purity is increased by 1.1 times of high level directional drilling after optimization, the gas concentration in the upper corner and return air flow in the working face decrease obviously and the gas extraction quantity in goaf has been significantly improved.