Proton-conducting electrolyte with Sm and Y co-doped BaCeO 3 (BaCe 0.8 Sm 0.1 Y 0.1 O 3-δ , BCSY) were prepared by sol–gel combustion method. The characterization of proton-conducting electrolyte was evaluated in saturated humidity by structure identification, such as X-ray diffraction (XRD). Anode-supported cell with configuration of Ni-BCSY/BCSY/SSC (Sm 0.5 Sr 0.5 CoO 3-δ ) were fabricated. The cell with cathode after two coats and sintering temperature of 1,050 °C showed superior electrical performance. It was achieved with open circuit voltage (OCV) of 0.99 V and P max of 220 mW/cm 2 at 600 °C when humidified (3 vol.% H 2 O) hydrogen as fuel and oxygen as oxidant.