In the present study, one-dimensional (1D) alpha-MnO2 nanowires with width of 50-60 nm, length about several micrometers have been successfully prepared under hydrothermal conditions in the presence of sodium carboxymethyl cellulose. The samples were characterized by X-ray diffraction, scanning electron microscope, superconducting quantum interference device and N-2 adsorption-desorption experiment. The magnetic measurement reveals that the alpha-MnO2 nanowires exhibit a ferromagnetic behavior at 5 K and a paramagnetic behavior at 300 K. The N-2 adsorption-desorption experiment shows that surface area is 160.4 m(2) g(-1), which is even larger than those of mesoporous nanostructures. At the same time, the possible formation mechanism for the formation of alpha-MnO2 nanowires has been proposed according to the experimental results. (C) 2011 Elsevier Ltd. All rights reserved.