In this paper, layered ZnO nanowall networks were directly grown on Al substrates using a hydrothermal method without predepositing seed layers. The individual ZnO nanowalls with a thickness of several nanometers and a size of several hundred nanometers were (002) surface dominated, in which the preferential growth direction of ZnO was suppressed. White electroluminescence devices were fabricated based on Au/polymethylmethacrylate/ZnO-nanowall (metal-insulator-semiconductor) structures. The chromaticity coordinate of the electroluminescence spectrum for the optimal device was calculated as (0.27, 0.34), which is close to (0.33, 0.33) of standard white light.