Abstract: Conducting oxides SrFeCo0.5Ox powder was prepared by nitrate sol-gel method. Thermal reaction of the gel during heating is investigated by DTA and the crystal structure and morphology of the calcined powder were characterized by x-ray diffraction (XRD) and transmission electron microscope (TEM) respectively. The results show that single perovskite oxide can be formed at 550°C with x=0.64. The oxide size particle is in nanometer grade and very uniform. As the calcined temperature increases up to 850°C, the phase of the sample still does not change but the particles size becomes 100 nm. The polymerization reaction of nitrates sol-gel is also discussed.