A large area of hematite (α-Fe2O3) nanowires has been successfully synthesized by thermal oxidation of iron foil in an atmosphere environment. The effects on the growth of nanowires have been systematically studied by adjusting the oxidizing environment as well as the reacting temperature and annealing time. The samples were characterized by scanning electron microscope (SEM), x-ray diffraction (XRD) and micro-Raman spectroscopy. Optimum condition was obtained by annealing sample at 600°C for four hours in oxygen-poor environment. Nanowires with dense, high aspect ratio and sharp tips were observed. The average diameter and length of the nanowires was 80 nm and 5μm, respectively.