Highly ordered Prussian blue nanowire arrays with diameters of about 50 nm and lengths up to 4μm have been fabricated for the first time by an electrodepositing technology with two-step anodizing anodic aluminum oxide films. X-ray diffraction and transmission electron microscopy measurement results show that the Prussian blue nanowires are dense, continuous, and highly crystalline with an fcc cubic structure of a = 10.14 A. The Mossbauer spectrum and infrared spectrum at room temperature indicate that the nanowires are ferric ferrocyanide: one kind of iron is Fe3+ with high spin and the other is Fe2+ with low spin. Magnetic property measurement results indicate that the Curie temperature of Prussian blue nanowire decreases as the average numbers of magnetic interaction neighbors is reduced.