Ionic-complementary peptides (ICPs) are well known for their strong propensity to form amyloid-like β-sheet fibrils. Here, we present the first example that α-helical based ICPs can self-assemble into a highly ordered fibrillar structure. Intriguingly, the individual α-helices in such fibrils are arranged shoulder-to-shoulder, making them distinct from conventional coiled-coil-based fibrils.