Sulfur-doped ZnO particles have been synthesized by hydrothermal method. The structural and optical properties were studied systematically by XRD, scanning electron microscopy (SEM), and photoluminescence. SEM results show that the particle is hexagonal and the average size decreases with increasing sulfur doping, which means a retardant effect of sulfur on the growth of S-doped ZnO. XRD results show that the lattice parameters increase with more sulfur, which means an effective sulfur doping and increasing strain. Optical characterization also shows that the effective sulfur doping will enhance the green emission and suppress the near bandgap emissions. (C) 2010 Elsevier B.V. All rights reserved.