Abstract: Combined with the gas geological data of Qidong coalfield, based on coalfield structural plane deformation coefficient, tectonic coal distribution feature and gas occurrence distribution characteristic, Qidong coalfield can be divided into four gas geological units. Taking Weimiao fault as a boundary, its north locates unit Ⅰ,Ⅱ, Ⅲ and the south is unit IV. By analysis, it found that the main factors affacting each unit gas occurrence are different. The first unit is seam depth, the second unit is fault structure, the third unit is igneous rocks and the fourth unit is the seam gas mass loss caused by stratum uplift.