This paper investigates the effect of coal-fired fly ash on dry CO2 sorbents as the supports and additives. For this purpose, various kinds of dry sorbent were manufactured by mixing fly-ash, the primary CO2 absorption components (NaOH and CaO) and water with their different combination. Thereafter, their CO2 absorption performance and the property were analyzed. As a result, variation of absorption efficiency and temperature as well as CO2 desorption of the sorbents are confirmed, which may be primarily ascribed to fly-ash addition to the sorbents. Particularly, fly-ash effect is strongly measured in the sorbent manufactured by mixing all four components (named WNCF sorbents). Absorption efficiency of WNCF sorbents at 550°C is 35.6% higher than that of flyash free sorbent and desorption is solely observed in WNCF sorbents. Fly-ash in WNCF sorbents leads to increase the dispersity of CO2 absorption components and decrease their particle size in the sorbents. In addition, fly-ash is used as the supports and pozzolanic reaction is hindered by NaOH in WNCF sorbent. Furthermore, CO2 desorption from the sorbents may be due to fly-ash. The interaction between fly-ash and CO2 absorption components substantially attenuate the strength between captured CO2 in CaO and NaOH.