Fe 0.3 Co 0.7 nanowire arrays were prepared by electrodeposition into the porous anodic aluminum oxide templates. The change of magnetic characteristic of the array with the diameter and heat treatment was investigated. It was found that the vertical magnetic anisotropy would drop lineally with the increase of the array diameter. Annealing can improve the coercively of the nanowire arrays. Coercivity as high as 3000 Oe was obtained in the sample annealing at 500℃. Magnetic properties of nanowire arrays may be developed to ultra-high-density recording on the quantum disk.