The growth of nickel-tungsten thin films on oxidized and nonoxidized carbon fibers is carried out under potentiostatic conditions in electrolyte solution containing nickel sulphamate and high amounts of tungsten. The electrocatalytic behavior of the deposits on different substrates (oxidized and nonoxidized carbon fibers) is compared. The kinetic of hydrogen evolution on Ni-W deposits is examined in sulfuric acid by cyclic voltammetry. The scanning electron microscopy and X-ray diffraction results show a more developed structure of Ni-W deposits on oxidized carbon fibers, as the domain size is two times less than on the nonoxidized carbon fibers. The impedance spectroscopy measurements show that Ni-W oxidized carbon fiber electrodes exhibit better electrocatalytic activity for the hydrogen evolution reaction (HER) than the Ni-W nonoxidized carbon fiber electrodes. The compact films show a higher catalytic activity in comparison with an island structure deposition. (c) 2006 The Electrochemical Society.