AbstractSingle-crystalline needle-shaped CdO nanostructures were synthesized using a chemical vapor deposition method and characterized using a variety of techniques. Devices consisting of individual CdO nanoneedles were fabricated and high conductance as well as high carrier concentrations was observed. The temperature dependence of the conductance revealed thermal excitation as the dominating transport mechanism. Our devices exhibited good sensitivity to both infrared light and diluted NO2 gas, indicating potential applications as infrared photo-detectors and toxic gas sensors.