In order to accurately predict coal and gas outburst risk at working face, a large number of measurements on basic gas parameters were taken on the basis of analysis and compilation of gas-geological data. The prediction indexes and critical values were determined with the study of the adsorption characteristics at 15# seam. With the prediction of outburst area, the prediction results were verified. This study shows that the adsorption ability of 15# seam is strong. Therefore, using a gas content 10.0 m³/t and absolute gas emission 4.0 m³/min as the prediction indexes and critical values is sound and rational. The study result has a useful reference value and is of significance for coal and gas outburst prevention.