Abstract: In order to study the effect of microwave on particles coal desorption rule, using the 1500W microwave to deal with the 1 ~3mm bituminous coal under different time conditions. Carried out the coal samples gas desorption experi ments under different adsorption equilibrium pressures by the adsorption and desorption test system in the lab, and compara tive analysed the instantaneous desorption quantity, cumulative desorption quantity, pore specific surface area and pore dis tribution. The results show that when the coal samples were heated, its pore structure and distribution were changed with the increasing of microwave irradiation time; under different adsorption equilibrium pressures, the coal samples′instantaneous desorption quantity and cumulative desorption quantity appeared inflection point in the third minute and fifth minute, which increased firstly, then decreased and then increased again after five minutes. And so were the pore specific surface area and volume that crucial for gas adsorption has the same rule. Finally, the microwave忆s influence mechanism to the desorption characteristic of the particles coal is discussed preliminary.