Electrical conductivity was measured in the solid and molten Snl(2)-Agl system between 70 and 85 mol % Agl. High conductivity and a broad region of solid solubility, placed between 80 mol %, 75 mol % and about 40 mol % Agl and 635.8, 380 and 559.8 K, respectively, was confirmed. The addition of the Snl(2) to the molten Agl is accompanied by a decrease in the electrical conductivity and an increase in the activation energy. Temperature dependences of the specific conductivity indicate a similarity between molten mixtures and solid superionic phases.