Abstract: Carbon nanoribbons (CNRs) are obtained by Fe catalyzed chemical vapor deposition on a silicon substrate using C2H2 as carbon source. The morphology and microstructure of this novel carbonaceous material was observed by field emission scanning electron microscopey, high-resolution transmission electron microscopy and Raman spectroscopy. It is found that CNRs are of the order of 100μm long, and most have a nearly rectangular transverse section several hundred nanometers wide and 30nm thick. The carbon layers of the CNRs have an uniform orientation perpendicular to the ribbon axis; the orientation is characterized to be the (002) direction. The microstructure of the CNRs arises from stacked open sheets of carbon layers, and the ridges of carbon layers are folded every several layers. The arrangement of carbon layers in CNRs is not very regular, and many stacking faults have been found. Potential applications of CNRs as energy materials are suggested.