A copolymeric membrane material containing an amine group for CO2 facilitated transport was synthesized by radical polymerization of acrylamide and maleic anhydride. The relative molecular weight and chemical structure of the copolymer were analyzed by viscometric measurement, elemental analysis, and FTIR. The copolymeric membranes were prepared. The sorption behavior as well as the permeabilities of the membranes for pure CO2 and CH4 were investigated. The results show that the copolymeric membrane possesses a higher permeability of CO2 and a lower pen-neability of CH4. The membrane displays a CO2 permeability of 5x10(-12) cm(3)(STP)/cm(2).s.pa, and a CH4 permeability of 2x10(-13) cm(3) (STp)/cm(2) s.pa. CO2 sorption behavior of the copolymeric membrane, which can be classified as a dual-mode sorption model, and CH4 sorption behavior of the copolymeric membrane accord with the Fickian diffusion model.