We present a study of the ferromagnetic properties of Gd doped ZnO nanowires (Nws) fabricated by means of a chemical vapor deposition process. The sample was grown with a Gd mole ratio 5% in a mixed Zn/Mn source under a constant O-2/Ar gas mixture flowing at 580 degrees C followed by annealing at 800 degrees C. We found that the magnetic properties of ZnO:Gd Nws are a function of the external magnetic field and temperature. An average value of the moment per Gd atom is as high as 3278 mu B as compared to its atomic moment of 8 mu B, showing that the ZnO:Gd Nws are an intrinsic diluted magnetic semiconductor. The unprecedented colossal moment is attributed to the effective Ruderman-Kittel-Kasuya-Yosida exchanging interaction. (C) 2012 Elsevier B.V. All rights reserved.