The electrochemical behavior of the anode RuO 2/TiO 2 during the electrolysis of sea water has been studied.The results showed that the RuO 2/TiO 2 anode could improve the current efficiency and decrease the energy consumption when the best condition corresponded to the current density of 100 mA/cm 2 and electrode gap s 5 mm. While the cathode potential reached 820~ 1450 mV(SCE), so the cathode would get electrochemical protecttion.