The development of functional nanofibers via self-assembly is an area of growing interest. Whereas self-assembly has been successful in creating nanostructures, the fabrication of hierarchical architectures from multiple functional components and the development of synergistic functions are emerging as challenging issues. In this chapter, various self-assembly approaches that are used to construct nanofibers are summarized. Self-assembly of amphiphilic supermolecules provides a key strategy to hierarchically fabricate multicomponent architectures. Amphiphilic pairs of nanofiber-forming molecules can be screened from a wide range of functional molecules, including biomolecules. As examples of nanofibers whose functions are dynamically controlled based on self-assembly, lipophilic one-dimensional metal complexes and their unique characteristics are introduced.