A new method is proposed to improve the adsorption properties of basic, macroreticular (MR) anion exchange resins by forming a material composite with chitosan. In this study, one strong basic and one weak basic MR resins were used as matrixes for the new composites. Chitosan was accumulated in the macropores of the resins, and breakthrough curves for adsorption of CO2 on the new adsorbents were measured. The resulting equilibrium and kinetic data were compared with those of the original resins. The composite of strong basic MR resin and chitosan showed a more than three times higher adsorption capacity for CO2 than the pure resin. On the other hand, the mass transport in the adsorbent slowed down due to a narrowing of the pores by deposited chitosan.