The Ruddlesden?Popper (RP) perovskitetype composite cathode material was prepared by a sol?gel method,and the performance of using it as a SOFC cathode was evaluated.XRD result shows that the composite material calcined at 1 200 ℃ was (La2/3Sr4/3)FeO4?(La4/3Sr8/3)Fe3O10 (LSF).At 400 ℃,the highest conductivity of the sample is 57.0 S/cm in air.At 800 ℃,the interfacial polarization resistance of the LSF electrode on La0.9Sr0.1Ga0.8Mg0.2O3-δ (LSGM) electrolyte is 0.198 Ω·cm2.Based on a single cell supported by a 300?μm?thick LSGM,the peak power density of the sample when used as a cell cathode was up to 670 mW/cm2 when used as the cathode of the cell, with no performance degradation for 50 h of continuous operation.Experiments show that the LSF cathode has excellent and stable electrochemical performance,and is a very promising cathode material for SOFC.