The electrical properties (electric conductivity, resistance of glasses to electrolysis, and electronic component of electric conductivity), density, and microhardness of the glasses are studied. The distribution of phosphorus throughout the polyphosphate anions is investigated by paper chromatography. The data obtained are used in interpretation of the concentration dependence of the electric conductivity. It is demonstrated that the electric conductivity of glasses in the Li₂O-P₂O₅ system is determined by the migration of lithium ions and protons. An increase in the Li₂O concentration decreases the proton contribution to the electricity transport.