Ordered semiconductor In2O3 nanowire arrays embedded in anodic alumina membranes were fabricated by electrodeposition and oxidizing methods. The X-ray diffraction and transmission electron microscopy indicate that the In2O3 nanowires with polycrystalline structure are uniformly assembled into the hexagonally ordered nanochannels of the anodic alumina membranes. The optical absorption band edge of In2O3 nanowires array exhibits a marked red shift with respect to that of the bulk In2O3, and depends on the post-heat treatment temperature. This is attributed to the oxygen vacancy in In2O3 nanowires and the interface interactions between the anodic alumina membranes and the In2O3 nanowires.