Successful application of related perovskite structure with K2NiF4-type materials, Pr1-xM1+xInO4 (M=Sr, Ba), as electrolyte for SOFCs is reported here for the first time. The highest open current voltage was 0.70 V for PrSrInO4 at 500°C and 0.77 V for Pr0.9Ba1.1InO4 at 600°C. Measured electromotive force using hydrogen and oxygen concentration cells reveal that Pr1-xSr1+xInO4 materials have proton conductivity, whereas Pr1-xBa1+xInO4 materials have both proton and oxide-ionic conductivity. Due to the high proton conductivity at lower temperature, the highest maximum power density in the Pr1-xSr1+xInO4 and Pr1-xBa1+xInO4 materials occurred at 500°C and 700°C, respectively. Both materials showed a decrease in OCV with increasing temperature, indicating that the optimal operating temperature was between 500°C to 700°C. Our results confirm that both materials are potential candidates as electrolyte materials for proton-conducting solid oxide fuel cells.