Abstract: A production system of electrolyzed water includes an electrolyzer the interior of which is subdivided into an anode chamber and a cathode chamber by means of a cation permeable membrane, a diluted brine tank arranged to store an amount of diluted brine to be supplied into the anode and cathode chambers of the electrolyzer, first and second water supply conduits connecting the brine tank to the anode and cathode chambers respectively, and first and second electrically operated hydraulic pumps provided on the first and second water supply conduits to supply the diluted brine from the brine tank into the anode and cathode chambers. To prevent an electric motor for the hydraulic pumps from corrosion caused by backward flow of electrolyzed water in the production system, the hydraulic pumps are deactivated upon the lapse of a predetermined time after application of the DC voltage to an anode and a cathode in the anode and cathode chambers has been interrupted.