The surface pressure-area isotherms of the monolayers of three kinds of amphiphilic derivatives of 8-hydroxyquinoline, N-hexadecyl-8-hydroxy-2-quinolinecarboxamide (I), 2-hexadecyloxycarbonyl-8-hydroxyquinoline (2) and 8-hexadecyloxy-2-quinaldinic acid (3) at an air-water interface on subphases with and without metal ion were investigated and compared with each other. Some information regarding the packing density and phase transition under different experimental conditions has been obtained. At the air-water interface 1, 2 and 3 can form metal complexes with Cu2+ ion present in the aqueous phase. The formation of complexes leads to changes in the area per molecule and the collapse pressure of thc monolayer. X-ray photoelectron spectroscopy analysis reveals Cu-ligand ratios in the LB films to he Lu. 1:1 for 1 and 2 and 1:2 for 3. Low-angle X-ray diffraction measurements showed the LB films of 1, 2 and 3 deposited from CuCl2 subsolution had good homogeneity and were Y-type bilayer films.