Abstract: In order to inspect the different critical value of the outburst danger prediction index between hard coal and soft coal in the Ding₆ coal seam for No.1 Coal Mine of Pingdingshan Mining Group, it made the prediction more targeted and effective. It used the research methods with the combination of the experiment of gas adsorption and desorption in the laboratory and theoretical analysis to conduct statistical analysis for experimental data, it carried out regression analysis and obtained the relationship of gas content W and gas pressure p, gas desorption index V₁ and Q₃, gas desorption index V₁ and gas pressure p, finally determined the critical values of gas content W and gas desorption index Q₃ of hard and soft coal outburst danger prediction index in the D₆ coal seam based on gas expansion energy. The critical values W of outburst danger prediction indexes of hard and soft coal were 5.55、4.93 m³/t. The critical values Q₃ of outburst danger prediction indexes of hard and soft coal were 0.20、0.26 mL/g.