Using electrochemical deposition onto porous anodic alumina membrane and subsequent ultrasonic treatment, we have obtained individual alumina nanotubes wrapping metal (Cu and Fe) nanowires with nanocrystalline structure, which are a kind of conventional nanocable prototype. Scanning electron microscope and transmission electron microscope observations and X-ray diffraction, energy dispersive X-ray fluorescence, and selected area electron diffraction analyses clearly show the formation of a composite nanotube structure. Its formation mechanism is discussed on the basis of microstructural characterization. Our experiments provide a useful way for fabricating low-cost and large-scale metal nanocables, which will be of important applications in nanodevices. (c) 2006 Elsevier B.V. All rights reserved.