Laβ-Al2O3 solid electrolytes were synthesized directly and their conductivities were measured in terms of ac impedance spectroscopy.The magnitude of conductivities is 10-6 to 10-2 S·cm-1.Based on these data, the dependence of the conductivity of Laβ-Al2O3 upon the temperature and the dopant concentration in the electrolytes was studied, and the activation energy for conduction was calculated, which is 0.89 eV to 1.02 eV from 450℃ to 1000℃. The ion transference numbers were also determined. Laβ-Al2O3 solid electrolytes were synthesized directly and their conductivities were measured in terms of ac impedance spectroscopy. The magnitude of conductivities is 10-6 to 10-2 S · cm-1. Based on these data, the dependence of the conductivity of Laβ -Al2O3 upon the temperature and the dopant concentration in the electrolytes was studied, and the activation energy for conduction was calculated, which is 0.89 eV to 1.02 eV from 450 ° C. to 1000 ° C. The ion transference numbers were also determined.