beta-Nerve growth factor (beta-NGF) is a 118 amino acid residue polypeptide with an important role in the survival and development of certain neuronal populations. A beta-NGF purified from cobra venom was crystallized by the hanging-drop vapor diffusion method. The crystals belong to the tetragonal space group P4(1)2(1)2 (or its enantiomorph P4(3)2(1)2) with unit-cell parameters a = b = 61.75, c = 154.40 Angstrom. X-ray data from these crystals were collected to 3.2 Angstrom resolution. Analysis of the packing density shows that the asymmetric unit probably contains two molecules. The self-rotation calculation implied that a beta-NGF dimer might exist in the asymmetric unit. (C) 2002 Elsevier Science (USA). All rights reserved.