L-Histidinium tetrafluorosuccinate (L-HFS), an organic nonlinear optical material has been synthesized and characterized by the elemental analysis, FT-IR, FT-NMR and X-ray diffraction studies. Solubility Of L-HFS was found to be higher in water than ethanol, Single crystals with dimensions 10mm x 6 mm x 3 rum were grown in an aqueous solution by the slow evaporation technique at 30 degrees C. The thermal stability of L-HFS has been analyzed by thermogravimetric and differential thermal analyses (TGA and DTA). The UV-vis spectral study reveals that the material has a wide optical transparency in the entire visible region with the lower cutoff wavelength at 235 nm. The phase matching condition was obtained by Kurtz powder second harmonic generation (SHG) efficiency test. The laser darn age threshold of the grown crystal was measured using a Q-Switched Nd:YAG laser (1064 nm). (c) 2007 Elsevier B.V. All rights reserved.