N-o-Nitrophenylsulfenyl(NPS)-l-α-amino acid(alanine, leucine, and phenylalanine) amides were dehydrated in POCl3-pyridine to yield the corresponding NPS-l-α-aminonitriles, which gave the l-α-aminonitrile hydrochlorides by treatment with anhydrous HCl. Optical purity of these nitriles was well retained.