Large-area (10 mm×10mm), vertically aligned α-Fe2O3 one-dimensional nanostructure (nanobelts and nanowires with controllable diameters) arrays are successfully synthesized by thermally oxidizing iron foil directly, which grow in the ［110］ direction of the hexagonal crystal. The morphology and microstructure of the synthesized arrays depend strongly on the growth conditions such as the oxygen pressure, temperature and reaction time. We found that the growth of α-Fe2O3 one-dimensional nanostructures follows a top-growth mechanism, in which the ratio of iron and oxygen atoms near the point of growth plays a key role.