Novel W-shaped porous ZnO nanobelt with the periodical junction angles of about 1188 and straight porous ZnO nanobelt have been successfully synthesized. The W-shaped structure growth changes from [0001] to [01 (1) over bar1] periodically. The straight nanobelt grows along [0001] direction. Both of the structures have smooth surfaces with high porous density. Based on our X-ray diffraction (XRD), electron microscopy and photoluminescence (PL) spectrum study, the growth mechanism of the special ZnO nanostructures is discussed, emphasizing the effect of alteration of the reactant concentration for two different morphologies. (C) 2008 Elsevier B. V. All rights reserved.