The electrical properties of TlSe and TlS compounds were studied in a constant and alternating measuring field when exposed to various doses of gamma radiation in the temperature range of 300…400 K. In a constant electric field, a decrease in electrical conductivity with time was detected. Complex impedance spectra were measured in the frequency range 20…106 Hz. It is shown that in the studied range of temperatures, frequencies and doses of γ-radiation, conductivity is ionic in nature. The electrical properties of TlSe and TlS crystals are determined by the conductivity of Tl+1 ions and the accumulation of charge carriers near the blocking silver electrodes.