The electrochemical properties and microstructure changes of Pr0.3Sr0.7Co0.3Fe0.7O3-delta (PSCF3737) were studied in this paper. It was confirmed through X-ray photoelectron spectroscopy and extended X-ray absorption fine structure analysis that the oxygen vacancy of PSCF3737 was lower and that the atomic distance between an oxygen atom and a neighboring atom (especially cobalt) of PSCF3737 was longer compared to those of Pr0.3Sr0.7CoO3-delta (PSC37). In addition, the surface reaction of PSCF3737 changed from a one-electron reduction mechanism to a two-electron reduction mechanism, which may lead to enhancement of the cathode performance. The area specific resistance of PSCF3737 was 0.11 Omega cm(2) at 700 degrees C after changing the fabrication conditions of the cathode in order to optimize the microstructure. A single cell test was performed using PSCF3737. A maximum power density of 315 mW/cm(2) at 575 degrees C was obtained. Published by Elsevier Ltd on behalf of international Association for Hydrogen Energy.