Abstract: The residual gas content values can directly affect the size of the gas content. When the residual gas content is calculated by the formula, for the different sampling points in the same mine, the measured a,b values have large differences, and no laws can be found. The gas content calculated by different a,b values have larger differences. On the basis of the effect analysis of adsorption constants, ash, moisture, porosity for the residual gas content, it is recommended that the measured statistical analysis of a,b values are used to determine a standard required, which cannot only reduce the measured number, but also ensures the accurate evaluation of gas extraction effect.