We have studied the ability of a novel molecule (diphenyl bis(octadecylamino) phosphonium bromide) to form both Langmuir films and Langmuir-Blodgett films under different experimental conditions. It has been found that this substance is capable of forming stable monolayers at the air-water interface and building up highly ordered LB films yielding Z-type LB films of high quality (transfer ratio of 1) which were characterized by UV-vis and IR spectra, electron microscopy, and X-ray diffraction.