AbstractChiralp‐nitrophenyl esters derived from the amino acid phenylalanine are cleaved by various histidine‐containing tripeptides and higher oligopeptides as catalysts at a micellar interface. It is assumed that the oligopeptides adopt an internally hydrogen‐bonded C7conformation when they dissolve into the micellar hydrocarbon phase. Chiral recognition is attributed to the formation of a hydrogen bond in the micellar hydrocarbon phase between one enantiomer of the ester and the peptide. It is important for the activity that the imidazolyl NH moiety of the His residue remains in the aqueous phase. The hydrophilic/hydrophobic balance, which determines the location of each of the amino acid residues of the peptide in the two‐phase system, can be controlled by varying the length and stereochemistry of the peptide chain and by attaching hydrophobic groups. The most selective catalyst is a tripeptide with the structure C4H9OC(O)‐L‐Phe‐L‐His‐L‐Leu. It cleaves thep‐nitrophenyl esters of N‐protected L‐ and D‐phenylalanine with an enantioselective ofkI/kD≈︁ 40. Further lengthening of the peptide chain with L‐Leu and L‐Ala residues and lengthening of the N‐protecting group of the catalyst decreases the enantioselectivity down tokI/kD≈︁ 6 for the penta‐peptide C12H25OC(O)‐L‐Phe‐L‐His