Abstract: The experiment in this case studide the traits of the absorption and desorption of coal to gas in alternating electric field(AEF)or sound field(SF).The research indicates that due to the operation of alternating electric field,the absorbing ability of coal to gas still follows well the rule of Langmuir Equation.In the case,with the field voltage climbing up,absorption constant a changes little while constant b keeps descending.Subjected to the operation of alternating electric field,the absorption and desorption of coal are weakened,and the desorbing process of methane coal is slowed down as well.In addition,the work of sound field lessens the absorbing ability of coal,and the gas absorption of coal minishes as sound intensifies.