CuO nanotube arrays and nanoflower films have been prepared in large area, respectively. Ordered CuO nanotube arrays were successfully prepared by heating the corresponding Cu(OH)(2) nanotube precursors in N-2, while CuO nanotube arrays with special nanoplate wall structure were obtained by heating the Cu(OH)(2) nanotube precursor in benzene solvent in autoclave solvothermally. Besides, CuO nanoflower film was directly prepared via the oxidation reaction of copper foil in autoclave hydrothermally. The samples have been characterized by X-ray diffraction, scanning electron microscopy and high-resolution transmission electron microscopy. These novel hierarchical CuO nanoarchitectures may be used as nanobuilding blocks for field emitters and other nanoelectronic devices. (c) 2006 Elsevier B.V. All rights reserved.