Single crystals of pure and lithium (Li)-doped L-arginine acetate (LAA) were grown by the slow evaporation technique. The effect of Li-doping on the growth, structural and optical properties of LAA crystal has been investigated. Powder X-ray diffraction studies confirm the crystal structure of the grown pure and Li-doped LAA single crystals. Various types of functional groups of the grown pure and Li-doped LAA single crystals were identified by the Fourier transform infrared (FTIR) spectroscopic analysis. The presence of Li in the grown crystal was confirmed by atomic absorption spectroscopic analysis. Electrical properties of the Li-doped LAA crystal were analyzed by AC impedance studies. The optical transmission study shows that the Li-cloped LAA crystal has good optical transparency in the UV and visible regions. (C) 2008 Elsevier B.V. All rights reserved.