Hydrophobic helical crowned peptides were synthesized and investigated on formation of an oriented thin layer of the helix peptides. The helix peptides in ethanol were incubated with a self-assembled monolayer (SAM) of ammonium-terminated alkanethiolate on a gold surface. The thickness of the peptide thin layer formed on the gold surface was determined by the surface plasmon resonance method. Complexation of the crowned peptide with the ammonium-terminated alkanethiolate facilitated formation of a peptide monolayer or multilayers on gold depending on the peptide concentration. The orientation of the helix peptide on the gold surface was investigated by FT-IR reflection-absorption spectroscopy. The tilt angle of the helix axis from the normal of the gold surface was estimated to be 28 degrees, when the crowned peptide complexed with the SAM of N-(epsilon-aminocaproyl)aminoethyl disulfide. This degree of orientation is more vertical to the surface than that of the complexed peptide with a SAM of 2-aminoethanethiol hydrochloride. Since the helix peptide without the crown ether unit was oriented in parallel to the surface, the crown ether/ammonium complexation should promote the vertical orientation of the helix peptides on the gold surface.