Abstract: Pt/Ta composite anode was tested at a constant current density of 200 mA/cm2.The electrochemical properties was characterized by potentindynamic polarization curves and electrochemical impedance spectroscopy (EIS) in seawater at different temperatures,in combination with SEM morphology observation and energy disperse spectroscopy (EDS).The results showed that Pt/Ta composite anode could load large current density.Electrochemical catalytic activity of the anode decreased relatively and the charge transfer resistance of Faradaic process increased evidently at low temperatures.The surface microcrak and the gas evalufron from working anode accelerated the dissolution of anode.