The mobilities and activities of ions in NaCl-glucose-water mixtures are probed by means of conductometry and potentiometry. A positive deviation of the limiting conductance from the Stokes-Einstein (SE) relation is observed. This striking effect is discussed in terms of ‘excluded volume’ concept for strongly heterogeneous liquids. A drastic difference between sodium cations and chloride anions is argued resting on measurements with ion selective electrodes. The microscopic structure of water-glucose solutions is thoroughly addressed by classical molecular dynamics (MD) method. The MD simulations reproduce qualitatively the main experimental findings; trends in the behavior of the Na⁺ and Cl⁻ ions are attributed to a noticeable difference in the structure and dynamics of their solvation shells.