Constructing hollow nanostructures is attractive for both fundamental research and practical applications. However, how to prepare hollow nanostructures in a simple, scalable, and cost-effective way still remains a great challenge. In this study, for the first time, the anodization technique is applied to construct hollow nanostructures. Specifically, hollow nanospheres of SnS/SnOx with a hierarchical porous structure are self-assembled directly on the Sn substrate, via a convenient one-step anodization method. When applied for sodium-ion batteries, the thus fabricated SnS/SnOx hollow nanospheres on the substrate readily serve as a binder-free electrode, delivering remarkably high cycling stability and rate capability.