Phosphotungstic acid (PW12) and 1,10-diaminodecane (1,10-DAD) molecules have been alternatively assembled on 3-aminopropyltriethyoxysilane modified quartz or silicon substrate to form multicomposite mutilayer thin films by the molecular deposition technique. Thus-obtained films were characterized by UV-visible, XRD, X-ray reflection (XRR), and XPS spectra. Results show that the layer-by-layer self-assembly of PW12 and 1,10-DAD leads to a well-ordered superlattice-layered structure with a d-spacing of 3.19 run, which exhibits extremely exciting photochromic properties. Based on the experimental data, a presumable interlayer structural model has also been suggested.