One-dimensional nanostructures of iron di-sulfide (FeS2) were synthesized in large quantities by solvothermal process at relatively low temperature. It is found that the anions of the iron source, temperature and the molar concentrations of the precursors in the solvent play an important role in controlling the morphology of the FeS2 nanostructures. The effects of these experimental parameters have been investigated by the SEM and TEM images. The crystal structures of the FeS2 nanoforms were studied by the XRD, HRTEM and SAED patterns and identified as cubic iron pyrite. (C) 2004 Elsevier B.V. All rights reserved.