A new nonlinear optical material, l-alanine acetate (l-AlAc) has been synthesized. Single crystals of l-AlAc have been grown by the slow cooling method. Bulk crystals have been grown with a solution pH of 3.0. The grown crystals were subjected to various characterization studies such as chemical etching, dielectric measurement, FTIR analysis, UV-visible spectrum and powder SHG test. The structure of the crystal was confirmed by single-crystal X-ray diffraction analysis. l-AlAc crystals exhibit better thermal and mechanical stability with improved optical properties. © 2004 Elsevier B.V. All rights reserved.