α-FeOOH nanorods were fabricated via a one-step hydrothermal approach using iron nitrate hydrate (Fe(NO3)3·9H2O) as iron source, cetyltrimethylammonium bromide (CTAB) as a template and acetic acid (CH3COOH) solution as solvent. XRD, SEM, TEM, and TGA were applied to characterize the samples. The as-prepared α-FeOOH nanorods are around 50 nm in diameters and 1 µm in length. The aspect ratio is 20. The XRD and TEM results indicated that both CTAB and CH3COOH were crucial for the formation of α-FeOOH nanorods. The heat treatment at the temperature of 250°C led to the transformation of α-FeOOH to α-Fe2O3, and the crystal phase transformation was completed at 340°C. The lower transformation temperature compared to bulk α-FeOOH could be attributed to the decreased size of the as-prepared sample.