An electrochemical method for preparing hydrogen peroxide by subjecting oxygen to cathodic reduction in a conductive reaction medium, the method comprising: (a) preparing a hydrogen peroxide containing halide ions, hydrogen ions and molecular oxygen a conductive reaction medium, and (b) electrolysis of said medium by a cathode and an inert anode at a cathode potential relative to the Hg/Hg↓[2]SO↓[4] reference electrode of about Within the range of -0.2 to about -0.75 volts, thereby reducing the molecular oxygen to generate hydrogen peroxide.