Continuous pearl-necklace-shaped In2O3 ceramic nanofibers with diameters around 30 similar to 100 nm have been fabricated by electrospinning combined with annealing process used indium nitrate and poly(vinylpyrrolidone) (PVP) as raw materials. The specific surface area of In2O3 ceramic nanofibers comes up to 100 m(2)/g. The morphology and chemical structure of the as-prepared and calcined samples were analyzed by scanning electron microscopy (SEM), thermal gravimetric analysis (TGA), high-resolution transmission electron microscopy (HRTEM), X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) techniques. The gas sensor fabricated by In2O3 ceramic nanofibers sintered at 700 degrees C has special gas sensing properties including high response and selectivity, fast response and recovery time to ethanol gas. [doi:10.2320/matertrans.M2010436]