The purpose of this paper is to study the difference of tectonic coal with different degrees of damage (DoD) in terms of gas adsorption, desorption and emission. To this end, by taking the 3# coal seam coal sample in Gaohe Coalfield as an example, the isothermal adsorption-desorption test was carried out in this paper to study the gas adsorption-desorption and emission law of tectonic coal with different DoD. The results show that with the DoD deepening of tectonic coal, the adsorption capacity of coal seam gas (CSG) in the geological structure area is better, and the CSG adsorption limit (adsorption constant a) increases; the coal seam gas desorption capacity is also better in the geological structure area, and the gas adsorption constant b decreases. Besides, the gas emission curve of fitting results indicate that Sun Chongxu Formula can accurately describe the gas emission process of tectonic coal. By comparing the numerical analysis results with the experimental results, it is found that the variation trend of the two is in good agreement.