We report successful growth of a new form of ZnO nanostructures, ZnO nanopetals at low temperature. This two-dimensional nanostructure is morphologically different from nanowalls. The flat and circularly edged nanopetals intersect each other. The thickness of nanopetals is uniform and about 30 nm. The nanostructure was produced using a simple catalyst-free chemical method based on anodic aluminum oxide (AAO) template. The growth temperature was 60 °C which is much lower than that required for growing ZnO nanowalls. The formation of the nanopetal network was induced by the porous alumina network on the surface of the AAO template.