Nanowires (NWs) of metal oxides (Fe2O3, CuO, V2O5 and ZnO) were grown by an efficient non-catalytic economically favorable method based on resistive heating of pure metal wires or foils at ambient conditions. The growth rate of iron oxide NWs exceeds 100 nm s−1. Produced NWs were typically 1–5 µm long with diameters from 10 to 50 nm. The produced metal oxide NWs were characterized by means of SEM, TEM, EDX, XPS and Raman techniques. The field emission measurements from the as-produced CuO NWs were found to have a threshold field as low as 4 V µm−1 at 0.01 mA cm−2. The formation mechanism of the NWs is discussed.