Abstract:It is generally acknowledged that geoelectricity is subsistent. It should be father studied that how geoelectricity affects stockpile and seepage of gas in coal seam and whether or not electric field can be used to speed the seepage of coal gas, thereby gas pumping rate of low pressure and low seepage coal seam. Adsorption and seepage characteristics of coal to methane under electric field have been studied. The effect of direct current electric field on adsorption characteristics of coal to methane rests with the competition of two factors which are the deep of adsorption potential well, is increased and coal temperature is raised by Joule heat effect. Adsorption ability of coal is increased when it is the leading factor that the deep of adsorption potential well is increased, but adsorption ability of coal is decreased when it is the leading factor that coal temperature is raised. Seepage ability of coal is increased under direct current electric field; Adsorption ability of coal is decreased and seepage ability of coal is increased under alternating electric field.