The solid fast ionic conductors are synthesized by sol-gel-hydrothermal method. The influences of the dispersion reagent, the mass of alkalinity and the temperature of calcinations on the surface description of nanometer-powder and electric conductivity are discussed. When PEG 12000 is used as dispersion reagent,the mass of alkalinity is 1.0%,the temperature of calcinations is 350℃, and the electric conductivity of Lithium Fast Ionic Conductor synthesized at the room temperature is 2.59×10^-3S?cm^-1.