In this communication, we demonstrate for the first time that nickel sulfide nanosheets array supported on Ni foam can be used as an inexpensive three-dimensional electrocatalyst toward the hydrogen evolution reaction in both neutral and basic solutions. The Ni3S2/Ni foam served as an inexpensive, highly active and stable electrode material for water electrolysis. It needs overpotentials of 220 and 396 mV to afford current densities of 10 and 100 mA cm(-2) in neutral media and needs overpotentials of 123 and 260 mV to afford current densities of 10 and 100 mA cm(-2) in basic solutions. Copyright (C) 2015, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.