The development of solid adsorbents and thin films for carbon dioxide adsorption is still considered as a big research area because carbon dioxide is one of main gases for greenhouse effect on earth and solid adsorbents have advantages for its efficiency and post-treatment than liquid adsorbents. Even though mesoporous materials as a powder formula have shown outstanding features in carbon dioxide capture, it is known that powder materials, as it is, have the limitation under any harsh processing conditions and working environments. Here, we present the preparation method for polymer composite films using several surface-modified mesoporous materials with high CO2 adsorption capacity and amine-containing polymers for various applications. Mesoporous materials were prepared with a cation surfactant and a P123 blockcopolymer as templates and tetraethylorthosilicate (TEOS) and 1,4-bis(triethoxysilyl)benzene (BTEB) were used as silica precursors. As an amine-functional group, N-[3-(trimethoxysilyl)propyl]-ethylenediamine was modified on the silica surface using post-grafting method. The homogeneous-heterogeneous nanocomposite thin films were prepared using styrene- co-acrylonitrile (SAN) copolymer, mesoporous materials, and dichloromethane (DCM) as a solvent by a facile solvent casting method. Carbon dioxide adsorption was analyzed using thermogravimetric analysis (TGA) microbalance at 25 °C under 1 atm.