The applicability of Ca-compounds involved in coal burnt ashes to dry gas sorbent for I ICI removal is experimentally studied. The experiments for HCl sorption are conducted bq employing different kinds of coal burnt ash discharged from a fluidized bed coal combustor (FBC), circulating fluidized bed coal combustor (CFBC), and pulverized coal combustor (PCC), The experiments were carried out with a packed bed of coal burnt ash 44-63 mm in mean diameter, through which the HCl gas of initial concentration of 1,000 ppm was made to flow under atmospheric condition in the temperatures range of 473 to 1,073 K. Experimental results show that the HCl conversion of coal burnt ash increase with the increment of the amount of Ca-compounds contained in the ash. There is an optimum temperature range between 673 and 873 K for HCl sorption for the employed ash samples. It is found that a part of Ca component did not show any reactivity for HCl sorption. Such Ca components, were considered to be in the form of melted amorphous silicate, oxide and sulfate, in accordance with the element distribution analysis on the surface of ashes by SEM/EDX.