This article reports on the fabrication of WO3 nanorods using an efficient straightforward synthetic technique, without a catalyst, and using a single precursor. The thermal dissociation of WO(OMe)4 at 700°C in a closed Swagelok cell under an air/inert atmosphere yielded W 18O49 nanorods. Annealing of W18O49 at 500°C under an air atmosphere led to the formation of pure WO3 nanorods. The obtained products are characterized by morphological (scanning electron microscopy and transmission electron microscopy), structural (X-ray diffraction analysis, high-resolution scanning electron microscopy, and Raman spectroscopy), and compositional [energy-dispersive X-ray and elemental (C, H, N, S) analysis] measurements. The mechanism of the formation of nonstoichiometric W18O49 nanorods is supported by the measured analytical data and several control experiments.