Zinc-doped SnO2 nanocrystals were prepared by a simple hydrothermal process. X-ray diffraction (XRD) patterns show that as-prepared samples are of tetragonal rutile structure of SnO2. Transmission electron microscopy (TEM) and field emission scanning electron microscopy (FE-SEM) characterizations confirm that the morphologies of zinc-doped SnO2 nanocrystals are "flower"-constructed nanorods. Photoluminescence (PL) measurement of the zinc-doped SnO2 crystals reveals a purple emission band centered at similar to 440 nm. The influences of the hydrothermal reaction temperature, the molar ratio of Zn2+ and Sn4+ as well as the concentrations of NaOH have been studied. The possible growth mechanisms of flower-like nanocrystals were discussed. (c) 2006 Elsevier B.V. All rights reserved.