The ZSM-5-type zeolites were prepared using three types of structure directing agent to investigate the effect of pore structure and PEI impregnation on the CO2 adsorption capacity. The CO2 capacity was primarily affected by the number of the adsorption site and the volume for trapping CO2. CO2 was well adsorbed inside the micropore with stronger electric field. The CO2 capacity increased with increasing amounts of impregnated PEI until PEI loading exceeded the total pore volume, because PEI predominantly occupied the pores of ZSM-5. The ZSM-5 with large surface area and total pore volume was the most favorable for amine-impregnated ZSM-5.