A 2,7-disubstituted phosphodiester-linked phenanthrene trimer forms tubular structures in aqueous media. Chromophores are arranged in H-aggregates. Incorporation of small quantities of pyrene results in the development of light-harvesting nanotubes in which phenanthrenes act as antenna chromophores and pyrenes as energy acceptors. Energy collection is most efficient after excitation at the phenanthrene H-band. Fluorescence quantum yields up to 23 % are reached in pyrene doped, supramolecular nanotubes.