Reduction process of Cu2O in an electric furnace has been investigated by means of radioisotope technique. Gu-64 in various chemical forms was used as a tracer. Radiometric measurements of samples and complementary chemical quantitative analyses allowed to determine degree of reduction and decoppering degree at all stages of reduction process. Also material balance has been drawn up and distribution of copper among the products determined. On the grounds of the data obtained the possible mechanism of the decoppering process and its kinetic parameters have been discussed.