Abstract: Abstract：Through the analysis of relevant literature review and geological data in Qian Jiaying mine.The geological tectonic factors are divided into five parts: buried depth contour, fault number, fault average drop, fault average length and fault density.By means of cluster analysis and analytic hierarchy process,five parts of geological structure factors are simplified,confirming the weights of geological structure factors at various levels in Qian Jiaying mine.Counting the index of gas outburst in different levels,combined with the gas dynamic phenomenon of -850m main cross cut area in Qian Jiaying mine,the critical value of gas outburst is to be 0.308 of geological structure in Qian Jiaying mine.This method quantifies the geological structural factors, and provides a way to analyze the geological structural factors.