Abstract: The major disaster of No. 5 coal seam of Shanyang Coal Mine is roof disaster and mining pressure under Ordovician limestone water-bearing layer. This research suggests the mine geological structure causes the difficulty of roof management and connects Ordovician limestone water-bearing layer with coal seam, which affects the mining in Shanyang Coal Mine. Grey fuzzy quantitative evaluation is adopted to process the main controlling factors of fault density,fault strength,fault fractal dimension value and folding plane deformation coefficient. Besides,the influential weight of the 4 main controlling factors is determined. Through the quantitative evaluation on the complexity of mine geological structure in Shanyang Coal Mine,a scientific basis is provided for the mining of No. 5 coal seam.