ZnO  single crystals were implanted at room temperature with 400 keV Tb+ ions at fluences in the range of 1 x 10(16) -2 x 10(17) ions/cm(2). Zinc oxide was chosen because of its potential for photonic applications as a semiconductor with high radiation resistance. After implantation and post-irradiation annealing, optical absorption was measured in a UV-VIS-NIR range and radioluminescence spectra were recorded at room temperature. Emission signals were generated by the Tb+ ion implants and intrinsic emission of the ZnO matrix were observed. The implant signal intensities were comparable with the host radioluminescence, even though the implants modify the surface of the crystal. It is suggested that the presence of Tb at high concentration generates stresses which influence the bulk material and also potentially forms precipitates or nanoparticles in the near surface region. Overall ion implantation of ZnO results in strongly modified luminescence. (C) 2007 Published by Elsevier B.V.