Recently, nanostructure perovskite oxides such as LaMO3 (M=Co, Ni, Fe, …) received attention in academic researches due to its catalytic properties. In this research, the LaCoO3 perovskite nanoparticles have been synthesized by single-step route via the sol-gel auto-combustion method. The precursors used in this method were lanthanum nitrate and cobalt nitrate, as metals sources dissolved in distilled water and also using PVP as a surfactant, Urea and glycine as an oxidizer. The sol formed at stirring stage at 60 °C continued by gelation through the water evaporation at 90 °C and then auto-combustion occurred. Product of combustion step was washed and centrifuged three times and later calcined at 600 °C for 2 h. As synthesized nanoparticles are characterized by scanning electron microscopy (SEM), X-ray powder diffraction (XRD), and particle size analyzer (PSA). The characterization results proved the synthesis of nanoparticles below 100 nm with perovskite structure in narrow size distribution by using this method. The purity and size of nanoparticles vary depending on the fuel and fuel to oxidizer ratio.