The bulk zinc oxide (ZnO) sample implanted O with implantation concentration of 5 x 10(19)/cm(3) was investigated by photoluminescence. A novel transition at emission energy of 3.08 eV at 77 K appears in the O-implanted sample. In order to find the origin of the novel transition, the O-implanted effects on the luminescence of ZnO bulk have been studied by first principle calculations based on the local density approximation. The theoretical results show that the novel transition at emission energy of 3.08 eV is attributed to O-antisite (O-zn) produced by O-implanted procedure. (c) 2006 Elsevier B.V. All rights reserved.