Hollow cage-like alpha-Fe2O3 microspheres with an average diameter of 500 nm and a shell thickness of 60 nm were successfully synthesized by a simple electrospinning technique using ferric nitrate (Fe(NO)(3)center dot 9H(2)O) and polyvinylpyrrolidone (PVP) as precursors. Fe(NO)(3)/PVP composite microspheres were calcined at high temperature to form an interconnected 3D hollow cage-like alpha-Fe2O3 structure. X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), high-resolution transmission electron microscopy (HRTEM), and magnetic measurements were used to characterize the morphology, structure, and magnetic properties of alpha-Fe2O3 microspheres. Based on the characterization results, a formation mechanism for electrospun hollow cage-like alpha-Fe2O3 microspheres was proposed. We also found that morphology-preserved conversion from alpha-Fe2O3 to magnetic Fe can be achieved during reduction reactions in H-2/Ar. The magnetic property investigation showed that the as-prepared hollow Fe nanostructures exhibit a ferromagnetic behavior and possess high saturation magnetization (M-s).