Abstract: In order to verify the influence law of water content in coal to gas adsorption and desorption characteristics, gas adsorption and desorption experiments were carried out in different equilibrium pressure conditions with different water content in coal. The experiment results show that the gas adsorption capacity decreases with increasing of water content in coal, it could be corrected by use of water content influence coefficient in practical application. With the water content increasing, the gas desorption became slower and the amount of gas remaining was greater. The water filled in the coal gap has inhibitory effect to gas adsorption and desorption.