Adsorption characteristics of methane, CO₂ N₂, 2-mmember mixture gases, electric acceptance matter, metal ion and organic substance by coal have been reviewed. Fractal BET adsorption model, experiential fractal Langmuir equation and Freundlich formula and the effect of electric field (EF) on adsorption of methane by coal have been discussed. A simple and reasonable kinetics equation on adsorption or desorption of methane by coal has been obtained. Methane adsorption capacity of coal decreases because of the existence of other gas. In EF, adsorption`s isotherm and kinetics don`t essentially changed, a constant is slightly changed, and b decrease.