An experimental study has been conducted to evaluate the formation of nano alpha-Al2O3 under various conditions, such as different calcining temperatures and emulsion ratios of aqueous aluminum nitrate solutions and oleic acid with a high-speed stirring mixer. Four batches of the precursor powders were calcined at three different temperatures of 1000 degrees, 1050 degrees, and 1100 degrees C for 2 h and a terminal product of nano alpha-Al2O3 powders was obtained. The products have been identified by X-ray diffraction (XRD), specific surface area measurement scanning electron microscope, and transmission electron microscope (TEM). The XRD results show that the phase of powders is determined to be alpha-Al2O3, indicating that the overall process has been effective. The optimum calcination temperature of the precursor powder for crystallization of nano alpha-Al2O3 was found to be 1000 degrees C for 2 h. The TEM image indicates that the particle grains have a sub-spherical shape with a mean size of 50-100 nm.