Abstract The Ag nanoparticles attached La 0.6Sr 0.4Co 0.3Fe 0.7O 3-δ (LSCF) perovskites were prepared by plasma method. The Ag nanoparticles with size of several nanometers evaporated from the Ag target were coated on the surface of LSCF powders with size range from 0.2 to 3 μm. The agglomeration of Ag particles annealed at 800 °C under inert gas of Ar and N 2 were rarely observed. The physical bond between surface Ag and core LSCF is effectively strong to prevent aggregation of Ag nanoparticles at high sintering temperature relate to synthesis route of cathode for solid oxide fuel cell (SOFC). The fuel cell showed relatively effective electric power density at operating temperature of 650 °C, though the extremely low Ag concentration.