A method for industrial production of nano-scaled WC powders has been proposed. In this work, WO2.9 is subject to pre-reduction, followed by jet-milling treatment. The precursor is then mixed with carbon black by ball milling, and directly reduced-carbonized to nano-scaled WC powders. The WC powders prepared at different carbonization temperatures were made into alloys and micro drills, revealing the influence of powder properties on the microstructure and properties of the alloys through comparative analysis. The results indicate that when WO2.9 powder is reduced at 700 °C for 1h and then jet-milled at a rotational speed of the grading wheel of 3500 rpm, the aggregates in the powder can be effectively broken, and the precursor powders with fine particle size and near-single phase can be obtained. In this way, the equipment exhibits relatively high productivity. By comparing the microstructure and properties of the alloy prepared from raw materials at different carbonization temperatures, it can be seen that if the carbonization temperature is too high, the average particle size of the powder increases and agglomeration appears in the microstructure. An increase in the average particle size of the powder will lead to an increase in the average grain size of the prepared alloys, thereby reducing the hardness and the wear resistance during service. In addition, the agglomerated particles in the powders can easily lead to abnormal WC grain growth in the microstructure of the prepared alloys, which reduces the bending strength.