Ce and Zr were doped in carbon aerogels (CAs) using the sol-gel polycondensation of resorcinol with formaldehyde with addition of Ce and Zr nitrate salts, followed by carbonization in N-2 and further activation in CO2. The doping changed the structure;of CAs that are representative mesoporous materials. The analysis of the pore structure showed that the Ce,Zr-doped CAs are highly microporous materials; the micropore volume and surface area are in the range of 0.16-0.70 cm(3) g(-1) and 500-2240 m(2) g(-1), respectively. It is noteworthy that the microporous Ce,Zr-doped CA have a monolith form as well as the mesoporous CA. The changes in the porous structure of the Ce,Zr-doped carbon aerogels during the activation were examined. Some mesoporosity was developed after activation for 5 h.