A facile vapor-solid strategy has been developed to prepare silica-sheathed metal micro/nanostructures with controllable shapes. As examples, silica-sheathed nickel nanowires (diameter similar to 50 nm), microcubes (edge length 1-3 mu m), nanocubes (edge length similar to 200 nm) with an epitaxial tail (diameter < 100 nm), and ID assembly structures of nanoparticles (particle diameter < 100 nm) as well as silica-sheathed cobalt and copper micro/ nanostructures are synthesized. The possible reaction and growth mechanisms of Ni/SiO2 Structures are discussed. The method is expected to be applied to a wider range of metals.