Coal-bed gas resources are huge in China.However

its scaled exploitation is limited due to unique occurrence status.Scientific methods are needed to identify the key geologic factors influencing its effective exploitation.In view of that the influencing factors are large in number and high in dynamic complexity

this paper established a model to identify and analyze the key geological factors based on rough set attribute reduction theory.First

sixteen original geologic factors were selected in respects of coal petrologic characteristics

coal seam features and geologic influences and were optimized according to the available data from 40 CBM wells selected for study in different regions of China.Then

decision data were constructed and attribute reduction of decision table was performed through rough set data analysis.Finally

sorting was performed according to their relative importance and the key influential geologic factors were identified.Eight geolo-gic factors including

geological structure type

in-situ stress

coal seam pores and fractures are relatively high in importance.Overall

external influential geologic factors have stronger power than internal ones such as coal seam and coal rock.Therefore

more attentions should be paid to the influence degree and action mode of the external geologic factors to enhance the level of mining gas hazard management in practice.