PURPOSE: To provide the electrode for corrosion prevention which can smoothly dissipate a generated gas to the outside field by positioning the other end of a gas vent pipe which is communicated at one end with the outside near to an insoluble metallic electrode of a bar shape, etc., in which the juncture to a flexible conductor is sealed against the outside.

CONSTITUTION: The above-mentioned insoluble electrode 4 is formed by coating the surface of a bar-shaped or pipe-shaped and more particularly a holeless pipe-shaped base body with an electrode active material. Namely, the base body consisting of Ti, Zr, etc., or the alloys thereof is coated with platinum group metals and/or the oxide thereof. the flexible conductor 1 for feeding electricity to said electrode 4 is connected to the base body and, for example, an insulating material is packed around the juncture thereof to prevent short circuiting of the juncture and the leakage of current. The other end of the gas vent pipe 11 which is communicated at one end with the outside is positioned near to the electrode 4. The gas generated on the surfacer of the electrode 4 by energization is guided through said pipe 11 and is released to the outside. As a result, the situation in which the energization is hindered or prohibited by the formation of the gaseous layer is averted.