A simple approach to fabricating tungsten trioxide robes was developed. Tungsten wires were heated at aronnd 800°С in a hnmid argon flow and hexagon-shaped robes with well faceted end and side surfaces resnlted. As observed with a scanning electron microscope (SEM), the robes were about 1um in cross-sectional dimension and 10um in length. The selected-area electron diffraction (SAED) pattern obtained in the transmission electron microscopy (TEM) study revealed that the robes were hexagonal tungsten trioxide (h-WO3) crystals. The formation of the well-faceted tubular structure is attribnted to the lateral coalescence of WO3 nanowires accompanied with a dehydration process.