Novel hybrid carbon-mineral composites were synthesized by mechanochemical activation of a mixture of tannin and bentonite in a ball mill with further pyrolysis in an argon atmosphere at 800 °C. Biomass-derived, cheap, nontoxic and abundant tannin was used as carbon precursors. The influence of the tannin content (Table 1) on the morphological, textural and structural characteristics of biochar has been described. It is worth noting that no solvents were used during synthesis process, providing a ―Green chemistry‖ technology. Furthermore, proposed pyrolysis allows synthesizing nanostructured hybrid materials retaining the structural advantages of bentonite (mesoporosity) and adding new structural characteristics due to a carbon component. The composites were characterized via N2-adsorption/desorption, TGA analysis, Raman and FTIR spectroscopy. The calculated BET surface area was 84, 127, 194, and 230 m² g for TBC-05, TBC-1, TBC-2, TBC-3, and control carbonized Tannin composite (TC), respectively. It was investigated that the increase in tannin content led to an increase in the volume of nanopores (from 0.6 to 0.8 cm3/g) with a simultaneous decrease in the mesoporosity of biochar (from 0.4 to 0.1 cm3/g) due to the formation of the carbon phase in the interplanar spaces of bentonite Figure 1. Pore-size distributions of composites Thus, different particle sizes, shapes, specific surface area and degree of graphitization characterize the assynthesized biochar. These characteristics show the effectiveness of the proposed approach to develop microporous and/or mesoporous structures in hybrid carbon-mineral composites.