Sepiolite and the sepiolite-based materials were studied in terms of carbon dioxide adsorption. The pore structure and the surface characterization of the obtained materials were specified based on adsorption-desorption isotherms of nitrogen measured at –196°C and carbon dioxide at 0°C. The specifi c surface area (SSA) was calculated accord-ing to the BET equation. The pore volume was estimated using the DFT method. Pristine sepiolite has shown the following value of SSA and CO2 uptake at 0°C – 105 m2/g and 0.27 mmol/g, respectively. The highest value of these parameters was found for material obtained by KOH activation of mixture sepiolite and molasses (MSEP2) – 676 m2/g and 1.49 mmol/g. Sample MSEP2 also indicated the highest value of total pore volume and micropores volume with a diameter up to 0.8 nm.