To provide a carbon sponge to obtain a highly efficient filter which adsorbs chemical substances such as VOC, as well as relatively large particles such as soil dusts without inhibiting flow of air or water.

The carbon sponge is formed by applying a carbon coating to its entire skeleton structure and then drying the coating. Since the sponge skeleton structure is thus entirely covered with a carbon powder mixture, the carbon sponge has a sponge-induced porous and soft structure as well as has carbon-induced adsorbing and far-infrared radiation characteristics.