Re-Ni cathodes catalytic activity towards hydrogen evolution reaction (HER) in the solution of sodium hydroxide is studied. Re-Ni coatings were deposited onto the surface of a copper substrate from ammonium-citrate solutions in the galvanostatic regime. The obtained deposits were examined by the complex of modern physical methods, namely: XPS, XRD, and SEM with X-ray microanalyzer. It was established that the full reduction of nickel species occurs during electrodeposition, while rhenium species electroreduction is incomplete. The obtained electrolytic deposits contained a high amount of hydrogen sorbed by them during electrodeposition. The increase in rhenium content in Re-Ni deposits caused the increase in their catalytic activity towards HER that was accompanied by Tafel slope decreasing. Heat treatment at 450 degrees C in vacuum resulted in a decrease in catalytic activity towards HER. It was suggested that high catalytic activity towards HER is caused by rhenium oxides included in the Re-Ni coatings. Heat treatment results in rhenium oxides reduction by sorbed hydrogen that causes a decrease in catalytic activity towards HER. (C) 2019 Elsevier Ltd. All rights reserved.