The coordination effects between chiral Schiff bases and metal ions can provide an effective strategy for fabricating chiral supramolecular self-assemblies. We studied the supramolecular self-assembly of the amphiphilic Schiff base enantiomer, 2-hydroxy-1-naphthylmethylamino-N,N'-bis(octadecyl)-L/D-glutamic diamide (L/DGJ), at the air/water interfaces by using in situ second harmonic generation linear dichroism (SHG-LD) technique combined with UV-vis spectroscopy and atom force microscopy. LGJ and DGJ monolayers can form mirror-image structures of each other at different interfaces, which can be mediated by metal ions. When Mg2+ and Zn2+ ions were added into the subphases, the L/DGJ monolayers self-assembled into a nanofiber-like structure and showed significant chirality similar to that at the pure water interface. However, when Cu2+ ions were added into the subphase, the chirality of the L/DGJ monolayer was destroyed because of the Cu2+ coordination effect. The degree of the chirality excess (DCE) value decreased with the increment of the concentration of Cu2+ in the subphase. Furthermore, when the surface pressure increased, the DCE value of Cu2+-L/DGJ complexes increased gradually, which indicated that the Cu2+-L/DGJ complex aggregated into a chiral supramolecular structure through lateral molecular packing.