Regularly arrayed nanocomposite system of zinc oxide/silicon nanoporous pillar array (ZnO/Si-NPA) was prepared by chemical vapor deposition utilizing Si-NPA as substrate, and the corresponding structure and photoluminescence properties were characterized. Our experimental results disclosed that all the pillars of ZnO/Si-NPA have a core-shell structure. Different from the red and blue emission from Si-NPA, two strong and wide emission bands were observed in the ultraviolet and blue-green ranges. These emission bands are attributed to the band-edge exciton transition of ZnO crystallites and two kinds of deep-level transitions originating from its intrinsic defects.