The general electrochemical behavior of molybdenum was investigated in sodium hydroxide solutions of different concentrations. The investigations were concentrated on the hydrogen evolution reaction on the metal surface. The effect of alkali concentration, cathodic potential and temperature on the rate of hydrogen evolution was evaluated. The results were compared with those obtained on copper or platinum metals. Different electrochemical techniques were used. Impedance measurements under open circuit conditions and under cathodic polarization were carried out. The experimental impedance data were fitted to theoretical data according to a proposed model for the electrode/electrolyte interface. The results have shown that molybdenum can be considered a good candidate for the cathodic hydrogen on a large scale and for long use. Copyright (C) 2013, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.