Nanosized alpha -Fe2O3 particles were prepared by thermolysis of iron(Ill) nitrate in a nonaqueous stearic acid medium. During the process, the composition of the samples were studied with the aid of infrared (IR) spectroscopy and differential scanning calorimetry (DSC). Thermolysis of the powders at 300 degreesC yielded alpha -Fe-O-3 particles with narrow size distribution in the nanometric range. The nanosized alpha -Fe2O3 particles were found to exhibit superparamagnetic characteristics.