As with most large manufacturing industries, by-product materials are generated. Cement kiln dust is a by - product material of cement manufacturing process. The aim of this paper is to investigate the properties of foamed paste made of CKD in addition of different percentages of cement. Compressive strength and thermal conductivity were determined. Sixty three cubes in three groups with different densities, amount of cement, CKD, water and foaming agent were cast. The results were encourage to use the Foamed( Cement kiln dust – cement) Paste (FCKDC) as an insulation materials. The results indicates' a comparable value for thermal conductivity which vary from ( 0.074- 0.3) W/mk.