Abstract: According to the problem that critical value of gas outburst prediction sensitive index of C₇₊₈coal seam in Pingqing Coal Mine is inconsistent with the real critical value and leads to local outburst prevention measures of engineering quantity increase and driving speed decrease, by historical prediction analysis, data statistics and analysis, laboratory research and field investigation method, the research identified that the main outburst prediction value of K₁ in C₇₊₈ coal seam is 0.6 mL(g·min^1/2), the prediction value of the reference index S value is 14 kg/m. Through the test of two stages that sensitive index critical value determined by the mine safety and efficient production meets production requirements, which can effectively liberate productivity and improve economic returns.