Molybdenum carbide (Mo2C) is one of most widely used transition metal carbides due to its remarkable physical and chemical properties, such as outstanding catalytic properties, good thermal stability, high hardness, excellent corrosion, and wear resistances. In the current work, a facile and feasible method was proposed to synthesize ultrafine molybdenum carbide powders with a high purity. Firstly, molybdenum trioxide (MoO3) powder was reduced with insufficient carbon black powder to remove oxygen from MoO(3)and generate a mixture of Mo2C and Mo. Then, the mixture was further carbided at 1100 degrees C or 1200 degrees C by carbon black to obtain pure Mo2C with an average particle size of 230 nm or 250 nm, respectively. A complete deoxidation at the first step is of significant importance for the precisely determining the amount of carbon addition in the carbonization step. The currently proposed method is a low-cost and efficient method to produce high purity and ultrafine Mo2C in a large scale.