Preliminary characterizations on Li isotope separation with Li ionic conductors were carried out. Three types of Li ionic conductors, which were a spinel Li4Ti5O12, a perovskite La0.55Li0.35TiO3 and a ramsdellite Li2Ti3O7 from the Li2O-TiO2 system, were selected. Electric conductivity and Li isotope separation efficiency were measured for each of the Li ionic conductors. It was shown from the results that each Li ionic conductor has sufficient electric conductivity and high Li isotope separation efficiency. Li isotope separation factors of three of the Li ionic conductors compare with that of the amalgamation process with mercury.