A facile approach to prepare iron nanostructures (nanowires, nanotubes, branched and multi-branched nanotubes) is reported by reduction of metal sulfide salts in the pores of an anodic aluminum membranes (AAMs) template with a back side Au sheet. The crystal structures and morphologies of Fe nanostructures are characterized by X-ray diffraction (XRD), field-emission scanning electron microscopy (SEM) and transmission electron microscope. The results indicate that the Fe nanostructures can replicate the inner architectures of the templates. The thickness of the Au film deposited on the back side of the AAMs and the inner structures of AAMs are the two key factors to determine the final morphologies of Fe nanostructures. This approach can be broadened to fabricate other metal nanostructures.