TeO₂ nanowires were synthesized on Au-coated glass substrates using a thermal evaporation method. Structural characterization showed that TeO₂ nanowires with high surface-to-volume ratio and large mass production had a single-crystal tetragonal structure. A gas sensor based on TeO₂ nanowires showed a quick response–recovery speed and a reversible response to n-propanol gas at low operating temperatures.