Self-propagating High-temperature Synthesis (SHS) was used to prepare complex oxide La0.7Sr0.3MnO3, which is used as the cathode in solid oxide fuel cells (SOFCs). Experiments show that La0.7Sr0.3MnO3 can be prepared via SHS under moderate conditions from a mixture of La2O3-SrO2-Mn-NaClO4-KMnO4，using NaClO4-KMnO4 as dual oxidants. The proper addition of the second phase oxidant KMnO4 makes the combustion wave movement stable. The product powders have an average particle size of 1-2μm and the particles are small aggregate. Pellets were sintered at 900 °C, 30 MPa for 10 min by spark plasma sinter (SPS). The electrical conductivity of sintered sample was 170 S•cm-1 at 1000 °C in air.