Hafnium carbide (HfC) is the most refractory compound known to mankind. A catalyst-assisted chemical vapor deposition method has been applied to synthesize contaminant-layer-free single crystalline HfC nanowires. The nanowires have diameter of 20-80 nm and length of several tens of microns. High-resolution transmission electron microscope images and electron diffraction patterns show that most of the nanowires grew in the < 100 > direction. Morphological and compositional analyses confirmed that the nanowire growth followed the vapor-liquid-solid mechanism. Field ion microscopy has also been used to reveal the surface structure of the tip of the nanowires.