Abstract: The production of high viscosity oil is a knotty problem in every oilfield.The electrothermal rod,which is developed by the Heating Power Unit of Research Institute of the Third Production Department of Dagang Oilfield,can solve the production problems caused by high viscosity oil.But in the field application,the corrosion of direct-current electrothermal rod is serious,and few corrosion occurs in the alternating-current electrothermal rod.Therefore,in view of the field situation,the author analyses and dis cusses the mechanism and degree of corrosion,anticorrsion method and its feasibility etc.,and Points out the developing direction of electrothermal rod.The author thinks that the leakage is the key reason to cause the electrochemical etching of DC electrothermal rod,and that adopting the AC electrothermal rod is the optimum way to deley corrosion.The conclusion of this paper has a reference value to the production of high viscosity oil using electrothermal rod.