Abstract: A bipolar electrolytic cell has a plurality of unit cells electrically aligned in series, each of the unit cells being divided into an anode chamber and a cathode chamber by an ion-exchange membrane, and each of the anode and cathode chambers having a supply pipe and a discharge pipe which are respectively connected at one end to common headers. The other end of each of the supply or discharge pipes in the anode or cathode chambers is inserted deep into the respective electrode chamber so that at least 50% of the electrical resistance of the liquid in each pipe exists in the electrode chamber, and the wall of the inserted portion of each pipe electrically insulates the liquid in the pipe from a liquid in the electrode chamber.