The hydrogen evolution reaction on the electrodeposited Ni-Mo alloy coatings, as well as their electrochemical properties in the NaOH solutions, have been investigated by the polarization measurements, cyclic voltammetry and EIS technique. it was shown that the Ni-Mo alloy coatings electrodeposited from the pyrophosphate-sodium bicarbonate bath possess high catalytic activity for hydrogen evolution in the NaOH solutions. Their stability in the 1 M NaOH at 25 degrees C under the condition of the reverse polarization was shown to be very good, while in the 33% NaOH at 85 degrees C (conditions of the industrial electrolysis) the electrodeposited Ni-Mo alloy coatings exhibited also high catalytic activity, but low stability, as a consequence of a deterioration of the alloy coatings. (C) 2008 International Association for Hydrogen Energy. Published by Elsevier Ltd. All rights reserved.