An electrolytic perovskite and method for synthesizing the electrolytic perovskite are described herein. Basically, the electrolytic perovskite is a solid that has an ion conductivity greater than 10^-5 S/cm in a temperature range of 0-400 C., wherein the ion is Li⁺, H⁺, Cu⁺, Ag⁺, Na⁺ or Mg²⁺. For example, Li_1/8Na_3/8La_1/4Zr_1/4Nb_3/4O₃ (5.2610^-4 S/cm) and Li_1/8K_1/2La_1/8NbO₃ (2.8610^-3 S/cm) are two electrolytic perovskites that have been synthesized in accordance with the present invention that have a high Li⁺ conductivity at 20 C. Both compositions have been confirmed in experiments to conduct Ag⁺ and H⁺ ions, as well. The present invention also includes a solid proton conductor that can be formed from the electrolytic perovskite by replacing the ions located therein with protons. The electrolytic perovskite and solid proton conductor can be used in a wide variety of applications or devices including, for example, a fuel cell, a membrane reactor, an amperometric hydrocarbon sensor or a steam electrolysis application.