Hydrogen production via high high-temperature steam electrolysis consumes less electrical energy than compared to conventional low low-temperature water electrolysis, mainly due to the improved thermodynamics and kinetics at elevated temperaturetemperatures. The elementalElemental powders of Cu, Ni, and YSZ are were used to synthesize high high-temperature electrolysis cathodecathodes, of Ni/YSZ and Cu/YSZ composites, by mechanical alloying. The metallic particles of the composites were uniformly covered with finer YSZ particles. Sub-micron sized pores are were homogeneously dispersed in the Ni/YSZ and Cu/YSZ composites. In this study, The cathode materials were synthesized and their Characterizations properties were evaluated in this study: It was found that the better electric conductivity of the Cu/YSZ composite was measured improved compared tothan that of the Ni/YSZ composite. Slight A slight increase in the resistance can be produced for in a Cu/YSZ cathode by oxidation, but it this is compensated offset for by a favorable thermal expansion coefficient. Therefore, Cu/YSZ cermet can be adequately used as a suitable cathode material of in high high-temperature electrolysis