The overall transport characteristics of different cationic species in Nafion(R) 117 membrane are presented. Equilibrium salt and solvent uptake by the membrane are determined in order to obtain the membrane chloride concentration, the membrane porosity and membrane water content. Conductivity measurements are investigated using impedance spectroscopy for sodium and proton cationic forms of the membrane. Electrical mobilities of sodium, nickel and silver ions are determined using an electrophoresis technique. By combining the results obtained from conductivity measurements, the sodium transport number is found in the Nafion(R) 117 membrane equilibrated with NaCl solution.