Abstract: The 8YSZ electrolyte solid sintering process from nanocrystalline powders were investigated. The density of YSZ was measured according to Archimedes’ principle. The line shrinkage was gottenby measuring the size of samples before and after sintering. The electronical conductivity was measured by four probes. And the microstructure was observed by SEM. The sintering temperature of 8YSZ decreases greatly because of the fine uniform spherical particles with a narrow size distribution and without hard aggregate. The YSZ electrolyte with high density, relative density more than 97%, low percent pore uniform crystal grains and high electrical conductivity up to 0.162Ω^-1cm^-1 at 1000oC are obtained at sintering temperature of 1450oC. It is especially suitable to be good electrolyte materials used in high temperature.