The conversion of coal fly ash into zeolites contributes to the mitigation of environmental problems and turns this by-product into useful material. In this work, zeolitic sorbents for CO2 adsorption were prepared by waste fly ash from Boryeong coal power plants through the alkali fusion method including hydrothermal treatment at various ratios of NaOH/FA and NaAlO2/FA. In addition, in order to improve the adsorption capacity for CO2 molecules a few metal cations were impregnated into the synthesized zeolitic sorbents through the ion exchange. The fusion step could decompose the fly ash to very small amorphous particulate zeolite forms. The fly ash was converted into Na-P1 type with 0.5 NaOH/FA and Na-A type from the ratio of 0.53, NaAlO2/FA. Although the crystallinity of Na-A increased with increasing temperature, Na-A was transformed into sodalite at 140℃. Thus, the optimum reaction temperature was determined to be 100℃. Alkali metal and alkaline earth metal cations were impregnated into the synthesized zeolite Na-P1 and Na-A through ion exchanged method. The completed zeolitic sorbents were applied to adsorption the CO2. As a result of the examination, Ca2+ was found to be the best for CO2 adsorption owing to its electrostatic interactions and acid-base surface properties. Keywords : Fly ash, Zeolite, Fusion method, Carbon dioxide, Adsorption