Single crystal of 2-[2-(4-diethylamino-phenyl)-vinyl)-1-ethyl-pyridiniumiodide monohydrate (EDEASI) has been synthesized by the Knoevenagel condensation reaction method. The synthesized compound was purified by successive recrystallization. Good quality single crystals were obtained by the slow evaporation method. The single crystal X-ray diffraction analysis has been carried out to determine cell parameters. It was found that the title material crystallize in the triclinic crystal system with space group PT. Crystalline nature of the grown crystal was identified from powder X-ray diffraction pattern. The FT-IR spectrum was recorded to identify the various functional groups present in the compound. The proton NMR spectrum has been recorded to identify the presence of particular hydrogen nuclei present in the synthesised material. The optical transparency range and cut off wavelength of the grown crystal have been identified by UV-Vis-NIR spectroscopy studies. ThemechanicaJ properties of the grown crystal were measured by Vicker's microhardness method. © 2015 Scientific Publishers. All Rights Reserved.