Single crystal of 2-[2-(4-methoxy-phenyl)-vinyl]-1-methylstilbazolium iodide (4MESI) was grown by the slow evaporation method. Single-crystal X-ray diffraction analysis reveals the formation of the title crystal. The density of the grown crystals was measured, and it was compared with theoretically calculated value. The FTIR and powder XRD of 4MESI were performed at room temperature. The different types of proton present in the crystal structure have been confirmed by NMR spectroscopic study. UV-Vis-NIR spectral studies reveal that 4MESI crystals are good optical transparency in the entire visible region. The photoluminescence spectrum of 4MESI shows violet and blue emission. Thermal stability and behavior of the grown crystal have been investigated by TG and DTG analysis. It shows that the grown crystal has melting point at 243°C. Mechanical hardness of the grown crystals was estimated by Vickers microhardness tester. The grown crystals were also characterized by chemical etching and dielectric studies, and the results are discussed in detail. © 2014 Akadémiai Kiadó, Budapest, Hungary.