Abstract <p>New ceramic materials that have ionic conductivity and can be used as components in various electrochemical devices are being actively developed. This study focuses on the electrical conductivity of a recently prepared layered perovskite-like oxide of La₂BaLu₂O₇, which has a two-layer Ruddlesden–Popper structure. Compounds with this structure exhibit ionic conductivity, whose level depends on the substitutions in the crystal lattice. It is found that the electrical conductivity in La₂BaLu₂O₇ has a mixed oxygen-ionic character, with ionic conductivity accounting for an average of 66.5% of the total conductivity.</p>