Co3O4 nanofibers were prepared by an electrospinning method and characterized by differential thermal and thermal gravimetric analyzer (DTA-TGA), X-ray diffraction (XRD), Fourier Transform Infrared Spectrometer (FT-IR), and scanning electron microscopy (SEM). Xylene-sensing properties of the as-prepared nanofibers were also investigated in detail. The results showed that the morphology of the as-prepared fibers was largely influenced by the calcination temperature. The Co3O4 nanofibers calcined at 500 degrees C exhibited the highest response to xylene in a wide concentration range. Moreover, Co3O4 nanofibers calcined at 500 degrees C also exhibited good selectivity, fast response (15 s) and recovery (22 s) rate at a low operating temperatures of 255 degrees C. These properties make the fabricated nanofibers good candidates for xylene detection.