The field emission properties of gallium oxide nanowires grown by thermal evaporation–deposition have been investigated inside the chamber of a scanning electron microscope. Turn on electric fields and enhancement factors have been determined for Sn doped nanowires. X-ray photoelectron spectroscopy measurements have been performed to calculate the work function of Sn doped Ga2O3. The results show improved field emission properties of Sn doped Ga2O3 nanowires, with a lower threshold field (below 1.0 V/µm). The obtained values are competitive with those achieved in other nanostructured materials, including carbon nanotubes.