Abstract: In order to study the adsorption characteristics of gas in heavy hydrocarbon coal,the isothermal adsorption processes of different component ratios with the binary gas CH4 -C2 H6 were experimented using the self-made adsorp- tion / desorption device of mixed gas. The quantitative relationship between the adsorption characteristic parameters of the mixed gas,the equilibrium pressure and the component ratio were analyzed,hereby,the adsorption prediction mod- el of binary gas was established. The results showed that under the same equilibrium pressure,the adsorption capacity of coal sample for one component C2 H6 was significantly higher than that of one component CH4 . With the pressure in- crease,the gas of C2 H6 was preferably adsorbed in the binary gas,and the free phase molar fraction rapidly declined. The molar ratio of adsorption and the adsorption equilibrium pressure showed an exponential function,and the parame- ters were linearly related to the component ratio. The error between the respective adsorption capacity and the experi- mental results was less than 5% through the new prediction model.