Semiconductor gallium nitride nanowires had been prepared by different catalysts using chemical vapor deposition. In, Fe, Ni, and Au nanoparticles were used in the growth of semiconductor GaN nanowires. Preliminary results indicate that the In, Fe, and Ni are efficient catalysts in the large-scale synthesis of GaN nanowires and the size of the nanowires depends on the size of catalyst particle. The nanowires have a diameter of 20-100 nm and a length of up to several hundreds of micrometers. The growth of GaN nanowires obeys the vapor-liquid-solid mechanism. However, no GaN nanowires were observed on the substrate when Au was used. It may be because of the poor solubility between Au and nitrogen. Au does not have any catalytic activity in this system. (C) 2003 American Vacuum Society.