Up to 91-layer arachidic acid (AA) LB (Langmuir-Blodgett) films containing photofunctional molecules, tris(1,10-phenanthroline) ruthenium(II) chloride hexahydrat (Ru(II)), were deposited by using Ru(II) aqueous solution as a subphase without any other ions. The AA LB films on Ru(II) subphase was characterized by the UV-visible, photo-induced emission spectra and low angle X-ray diffraction. Both absorption and fluorescence spectra have shown that the LB films have good optical properties in visible region. As many as five Bragg's diffraction peaks were observed in the 2 theta angle range of 1 to 10 degrees, indicating that the LB films have good arrangement with the Ru(II) ions on the end of the AA chain homogeneously.