High-content Fe hollow nanostructures from nanotubes (NTs) to nanorings (NRs) have been successfully fabricated by reduction of alpha-Fe2O3 hollow nanostructures at designated temperature. We investigated the influence of reduction condition on the structure and property of the products. With increasing reduction temperature, alpha-Fe2O3 with rhombohedral phase could be converted to cubic inverse spinel phase Fe3O4. Thereafter the phase was converted to the dominant cubic Fe preserving the same morphology. The highest M-s is 126 emu/g and 123 emu/g for 70 nm NRs and NTs reduced at 450 degrees C, respectively. Our results provide a general strategy of reducing single-crystalline alpha-Fe2O3 hollow nanostructures to get high magnetization which is required for many applications. (C) 2013 Elsevier Ltd. All rights reserved.