The synthesis and performance of (La0.75Sr0.25)(1-x)Cr0.5Mn0.5O3 (x=0.0,0.1,0.2) (LSCM) cathode powders of solid oxide fuel cells by gel-casting and solid-state reaction methods were investigated. Differential thermal analysis and X-ray diffraction analysis indicate that the phase formation temperature of LSCM powders synthesized by the gel-casting technique is 50-100 degrees C lower than that by the solid-state reaction method. The reason is related to the homogeneously distributed and immobilized precursor particles in a polymeric network, achieved during the cross-linking and gel formation steps. The LSCM cathode prepared by the gel-casting powder is shown to have a much higher electrochemical activity for the O-2 reduction than that by the solid-state reaction powder. However, significant A-site nonstoichiometry (0.1 or higher) should be avoided to prevent the formation of a secondary (MnCr2)O-4 spinel phase. (c) 2007 The Electrochemical Society.