The electrochemical measurement is a promising method available to perform actual continuous in-situ monitoring of corrosion degradation in nuclear power plants.The tungsten/tungsten oxide electrode which can be prepared by simple methods and owns high mechanical strength and robustness has advantages for applications as the reference electrode used in high temperature aqueous environments.Four methods were used to form tungsten oxide on the surface of tungsten and their electrochemical characteristics were investigated in a series of H3BO3 and LiOH solutions.The results showed that all tungsten/tungsten oxide showed linear response to pH values.Tungsten oxide prepared by immersion in HNO3 solution was composed of loose plates oxide and tended to spall off from the metal matrix.While tungsten oxide prepared by heat treatment consisted of compact particles and is relatively stable during the test period.Electrodes made by cyclic voltammetry and immersion in test solutions were too thin to be observed by SEM and their electrical behavior was similar after a period.The thermodynamics of tungsten/tungsten oxide electrodes were obtained by calculating the potentials of the different oxides of tungsten and comparing them to the experimental results.