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The rare earth oxides (REO) doped molybdenum powder was prepared by solid-solid doping, solid-liquid doping and liquid-liquid doping, respectively; afterwards, the powder was sintered by spark plasma sintering and traditional sintering combined with cold isostatic compaction method for fabricating REO-Mo cermet cathodes. OM and emission property tests were used to research the microstructure and the secondary electron emission properties of the samples. The results show that the emission properties of the material can be enhanced through the uniform distribution of rare earth oxides and the refinement of structure. The activation temperature can be decreased greatly by annealing in hydrogen at high temperature, and the secondary emission yield is also enhanced apparently.