Mesoporous carbon and silica containing composites are prepared based on the co-assembly of a suitable surfactant in a liquid medium. When a low molecular weight carbonizable polymer and a silica precursor are added to the surfactant solution, a mixture of distinct phases of the materials is formed after solvent evaporation. A polymer/silica solid composite with highly organized mesopores is obtained after surfactant removal. This product has utility as a catalyst support or gas absorbent. And the polymer-silica composite can be easily converted successively to a mesoporous carbon-silica composite and to a bimodal mesoporous carbon material.