Tree-like SnO2 nanowires have been grown by a vapor-solid process using a milled SnO2 powder as the evaporation source. Phase, structural evolution and chemical composition were investigated using X-ray diffraction (XRD), x-ray spectrometry (EDS), and scanning electron microscopy (SEM). The process yields a large proportion of ultra-long rutile nanowires of 50-150 nm diameter and lengths up to several tens of micrometers. High-resolution transmission electron microscopy (HRTEM) shows that the SnO2 nanowires are single crystals in the (101) growth direction with scattered smaller crystals or nanowires as the tree branches. The SnO2 nanostructures were also examined using Fourier transform infra-red (FTIR) and photoluminescence (PL) spectroscopy. A strong emission band centered at 548 nm dominated the PL spectrum of the tree-like nanowires. Crown Copyright (C) 2010 Published by Elsevier B.V. All rights reserved.