Nanometer-sized zirconium oxide (ZrO2) fibers with diameters about 200 nm have been synthesized by calcination of the zirconium oxide/poly(vinyl acetate) (PVAc) composite nanofibres prepared by sol-gel processing and electrospinning technique. The general morphology of the nanofibers has been studied by scanning electron microscopy (SEM) and atomic force microscopy (AFM). The crystalline phase evolution as a function of calcination temperature was studied by X-ray diffraction patterns (XRD) of the nanofibers, which showed that the samples after calcination at 500 degrees C and 750 degrees C showed the presence of tetragonal phase along with some traces of monoclinic zirconium oxide. After calcination at 1000 degrees C, only monoclinic phase was identified in the XRD patterns. The formation of pure zirconium oxide was further confirmed by FT-IR spectra.