Vertically oriented well-aligned ZnO nanorods were successfully fabricated on a ZnO/porous silicon layer by low-temperature chemical bath deposition. A single, sharp (002) peak revealed by X-ray diffraction confirmed the vertical growth and crystalline quality of the ZnO nanorods. The average crystallite size and compressive strain of the ZnO nanorods were determined to be 34nm and −0.0363%, respectively. Field-emission scanning electron microscopy indicated that the fabricated ZnO nanorods grew vertically from the substrate. Transmission electron microscopy determined the average diameter and the length of the ZnO nanorods to be 30 and 220nm, respectively. Photoluminescence spectra exhibited a strong, sharp UV emission peak at 381.75nm.