beta-Ga2O3 nanofibers of sub-50 nm diameter are formed using a GaCl3, polyvinylpyrrolidone, and deionized water solution via an electrospinning method. The as-electrospun amorphous nanofibers turn into polycrystalline nanofibers of monoclinic phase after annealing at 900 degrees C for 6 h. Material properties of the nanofibers are investigated using X-ray diffraction, scanning electron microscopy, transmission electron microscopy, and X-ray photoelectron spectroscopy. In addition, the nanofibers' optical bandgap is measured via the direct-bandgap model. Unlike the conventional ethanol-contained solvent and Ga(NO3)(3), the ethanol-free solvent and GaCl3 led to sub 50-nm diameter Ga2O3 nanofiber that could be applied to power devices (rather than a conventional 3-dimentioinal beta-Ga2O3 substrate) to effectively remove the heat generated during device operation.