PURPOSE: To obtain activated carbon having a network structure, continuous pores and superior adsorbing power by carbonizing and activating a porous body consisting of synthetic polyvinyl acetal resin, a resin convertible into glassy carbon and fine ceramic powder.

CONSTITUTION: PVA, phenolic resin and fine ceramic powder are mixed with a pore forming material and reacted with a cross-linking agent such as formaldehyde to obtain a porous body consisting of synthetic polyvinyl acetal resin and fine ceramic powder, and the porous body is combined with a resin convertible into glassy carbon by thermal decomposition such as phenolic resin. The resulting composite porous body is optionally carbonized by calcination in a nonoxidizing atmosphere, and it is simultaneously carbonized and activated by heating to 500W1,200°C in an atmosphere of steam or gaseous CO2 to obtain activated carbon having a network structure, continuous pores, a uniform pore size distribution, high shape retentivity, large specific surface area and superior adsorbing power. The carbon causes a small pressure loss when a fluid is passed.