In this work, high-quality ZnO nanowire arrays with controllable degrees over size, orientation, uniformity and periodicity are fabricated on GaN substrates with focused ion beam etching and lowtemperature hydrothermal method. Experimental results revealed that the patterned holes (i.e., shape, depth, size and period) have decisive impacts on the morphology of resulting arrays. Optimal conditions and ordered arrays are obtained in terms of functionality analysis for both patterned holes and hydrothermal method. A possible mechanism is proposed to interpret the growth process in and out of the pattern holes. Results show that this hybrid method exhibits good reproducibility for the fabrication of high-quality ZnO nanowire arrays with great potentials. (C) 2014 Elsevier B.V. All rights reserved.