Single crystalline copper oxide nanoribbons were synthesized via a surfactant-assisted hydrothermalroute. The resulting CuO nanoribbons contain substantial amounts of nanorings and nanoloops. Highresolution TEM analysis identified CuO nanoribbons growing along the  direction. CuOnanoribbons exhibited excellent sensing performance towards formaldehyde and ethanol vapours withrapid response and high sensitivity at low operating temperatures. We found that the loading of a smallamount of Au or Pt nanoparticles on the surface of CuO nanoribbons can effectively enhance andfunctionalize the gas sensing performance of CuO nanoribbons.