Pechini sol–gel method has been employed for the preparation of nanocrystalline La0.8Sr0.2FeO3 perovskite. The synthesis procedure was optimized by varying the calcination temperature. The results revealed the decomposition of the resin precursor and confirmed the formation of the perovskite phase starting at 600°C with spherical morphology (<50nm) and subsequently increased crystal size at higher temperatures, in all cases with a structure consisting of agglomerates. The presence of pores formed by the combustion of the resin precursor was appreciable in perovskites obtained at 600 and 850°C, whereas sintering was observed at 1000°C.