Self-assembled multilayer film of a cationic oligo(p-phenylene vinylene) derivative, 4,4'-(1,4-phenylene dithenylene)-bis-(N-methyl pyridinium iodide) (OPV), and the anionic poly(sodium 4-styrene sulfonate) (PSS) was fabricated by using electrostatic interactions as driving force. X-ray diffraction patterns (XRD) indicate that this method can effectively eliminate the crystallization of OPV. UV-VIS spectra reveal that OPV molecules tend to form H-aggregate in the multilayer film. Fluorescence spectral results show that the luminescent peak of the OPV in multilayer film underwent a blue shift about 80nm compared with that of OPV in solid state. The emission intensity of OPV in the multilayer film is much stronger than that of OPV in spin-cast film due to the isolation of OPV in the film by PSS.