Crystalline gallium nitride nanoribbon rings have been fabricated through a simple catalytic reaction using metallic Ga as source materials. The as-synthesized products were characterized using scanning electron microscopy, energy-dispersive X-ray spectroscopy, X-ray powder diffraction, transmission electron microscopy, and selected-area electron diffraction. The results revealed that the products are pure, crystalline GaN with hexagonal wurtzite structure. The widths of the nanoribbon rings were in the range of 150-350 nm and the diameters were 3-8 mum. The formation mechanism of nanoribbon rings was discussed tentatively. (C) 2003 Elsevier B.V. All rights reserved.