The design, synthesis, and structural studies of aromatic foldamers based on oligo(phenanthroline dicarboxamide)s that displayed supersecondary structure motifs have been described. Governed by a combined conformational restriction, the foldamers adopted well defined and compact 3D structures, which have been validated by UV/Vis, NMR spectra, and X-ray crystal analysis. The results presented here would offer a useful route for the de novo design of aromatic oligoamide foldamers with distinctive structural architectures.