Helices in proteins play an important role in a variety of fields such as biology, medicinal chemistry, and organic chemistry. Therefore, stabilized helical peptides have been developed in recent years. As tools for peptide-helix stabilization, non-proteinogenic amino acids such as α,α-disubstituted α-amino acids, cyclic β-amino acids, and cross-linked side chains are often utilized. Herein we report secondary structural control of short peptides using L-amino acids, D-amino acids, α,α-disubstituted α-amino acids, and cross-linked side chains. Furthermore, we applied the stabilized short helical peptides to the catalytic enantioselective epoxidation of α,β-unsaturated ketones, to the inhibitors of vitamin D receptor(VDR)-coactivator interaction, and to the efficient cell-penetrating molecules.