Large-scale, high-density gallium nitride nanowires were successfully synthesized by the direct reaction of gallium and ammonia using gold as initiator. The as-synthesized product was characterized by XRD, SEM, TEM, SAED, and EDS. The results showed that the product is hexagonal wurtzite GaN with high purity. The nanowires have diameters in the range of 60–100 nm and are a few tens of micrometers in length. A remarkable feature is that catalyst particles were observed at the ends of the nanowires, indicating that the growth process can be controlled by the vapor–liquid–solid mechanism. The present results revealed that gold is an effective and advantageous catalyst for the growth of GaN nanowires.