[en] We report the optical properties of the cyanine dye molecule thin film fabricated by a layer-by-layer method. While the absorbance and the film thickness increase with the dipping time, the use of a multilayer structure enables fabrication of the thin film without the creation of the molecule bundle that suppresses light scattering and the large absorbance obtained for the shorter dipping time. Exciton dynamics are studied by using a pump-probe technique; the signal shows two decay components in the multilayer sample that originate from the fast intramolecular relaxation and from the slow exciton relaxation. The temporal profiles show at the high signal-to-noise ratio. These results indicate that the thin film without the creation of the molecule bundle fabricated by the layer-by-layer method can be used for ultrafast all-optical switches. (paper)