An electrochemical method for preparation of bimetallic nanoparticles is described. Gold nanoparticles were first self-assembled on gold film electrode by 1,6-hexandithiol via Au–S bond. A [PtCl6]2- layer was then adsorbed onto the prepared gold nanoparticles and Au@Pt nanoparticles could be obtained through pulsed potentiostatic reduction. The structure and nature of the resulting Au@Pt nanoparticles were characterized by scanning electron microscopy, transmission electron microscopy, UV–visible spectroscopy, cyclic voltammetry and electrochemical impedance spectroscopy techniques. The electrocatalytic activity of Au@Pt bimetallic nanoparticles toward hydrogen evolution reaction (HER) has been investigated. The kinetic constants for HER were comparatively investigated for different modified electrodes by hydrogen evolution voltammetry.