In this paper, we report a simple and large-scale fabrication of CuO array films with different nanostructures grown on copper foils. CuO nanotube and nanorod array films were synthesized through the dehydration of the nanostructured Cu(OH)2 arrays in flow of N2, which are prepared in an alkali solution at a low temperature without using any templates and surfactants. The obtained CuO nanotube and nanorod array films retain similar morphology to that of the Cu(OH)2 precursors. While CuO nanosheet and nanobelt array films were prepared directly in the alkali solution. The evolution of the nanostructures as a function of the reaction conditions has been revealed, from nanorods of Cu(OH)2 to nanotubes of Cu(OH)2 to nanosheets of CuO to nanobelts of CuO. Experiments show that the growth temperature plays an important role in the formation of well-aligned Cu(OH)2 nanostructured array films on copper foil. The samples are characterized by XRD, SEM and TEM.