Submicron-sized cube-like α-Fe2O3 agglomerates were successfully fabricated via hydrothermal technique. The material showed a high reversible capacity of 900.2mAhg−1 and excellent capacity retention of 88.9% after 35 cycles at a current density of 40mAg−1. The initial columbic efficiencies of the as-prepared powder were 82.65 and 80.57% at current densities of 40 and 80mAg−1, respectively, which is higher than that of other α-Fe2O3 electrodes reported so far. We believe that the small crystal size and the high structure stability are responsible for the drastic improvement in initial coulombic efficiency and reversibility.