The influence of tea and coffee flavonoids (-)-epicatechin (EC) and (+)-catechin (C) on the effect of gamma-irradiation of DNA molecules in solutions was investigated. The concentrations of these and other components in different samples of black and green tea were analyzed by the capillary electrophoresis. It was determined from the experimental data obtained by different methods (circular dichroism and UV spectra, viscosimetry and optical investigations) that C and EC do not form complexes with DNA in solutions. It was shown that C and EC have radioprotective properties, being scavengers of the water radiolysis products.