The effect of gamma radiation on sorption of 85Sr2+ on trace manganese dioxide and on precipitation of 131I– with Ag+ ions has been studied. The transition of both radionuclides into the solid phase by sorption and precipitation was found by measurement of the self-diffusion coefficients of 85Sr2+ and of 131I–. The gamma radiation had negative effect on sorption and precipitation and also affected the ionic state of 85Sr2+ and of 131I–.