Cu-Al-O nanofibers are synthesized by an electrospinning method. After electrospinning process, these nanofi bers were thermally treated at different temperatures from 900 to 1 100?. The morphology and crystal structure of thefi bers were analyzed by scanning electron microscopy and X-ray diffraction. Thick fi lm gas sensors were fabricated by spinning the nanofi bers on a ceramic substrate with Au-Pt interdigitated electrodes. These sensors exhibited high ozone sensing properties at room temperature. When the sensors were exposed to 100 ppm ozone, the response time was about 2.74 s, and the recovery was about 12.68 s.