Silicon carbide nanowires were grown by heat treatment of the films at $1200^{circ}C$ after amorphous SiC thin films were deposited on graphite substrate by radio frequency magnetron sputtering at $600^{circ}C$. It was confirmed that SiC nanowires with the diameter of 20-60 nm and length of about 50nm were grown from Field Emission Scanning Election Microscope (FE-SEM) and Transmission Election Microscope (TEM) observation. The diameter of nanowires was increased as heat treatment time is increased. The nanowires were identified to ${eta}$-SiC single crystalline from X-Ray Diffraction(XRD) analysis. It was observed from this study that deposition temperature of samples was critical to the crystallization of nanowires. On the other hand, the effect of deposition time was insignificant.