alpha-FeOOH nanorods have been prepared at room temperature by an environment-friendly microemulsion approach. X-ray diffraction and transmission electron microscopy revealed that the single-crystalline orthorhombic alpha-FeOOH nanorods are 8.2 +/- 1.5 nm in diameter and 106 +/- 16 nm in length. Furthermore, the mechanism for the formation of alpha-FeOOH nanorods is preliminarily presented. This method may be widely used for reference to fabricate other inorganic one-dimensional nanostructured materials and easily realized in industrial-scale synthesis. (C) 2006 Elsevier Ltd. All rights reserved.