Samples of porous matrices with the surface of channels (pores) modified with carbon were prepared on the basis of nanoporous sodium borosilicate glasses (SBS) with average pore diameter of 6 ± 0.5 (PG6) nm. A procedure has been developed for introduction of carbon into the PG6 channels from an aqueous solution of sucrose with its subsequent thermal decomposition. X-ray diffraction studies of the state of carbon in the pores of the obtained modified matrix have been carried out. The small-angle neutron scattering method is used for study of internal spatial arrangement of these matrices and to obtain information concerning to the state of channel surfaces in these samples. A combined analysis of the data obtained by X-ray diffraction and from the results of small-angle neutron scattering have shown that the process of thermal decomposition of sucrose in the channels led to the formation of amorphous carbo layers on the internal surface of the channels (pores) in these glasses, i.e. the "matrix-porous space" interface was being modified.