Three-dimensional (3D) ZnO nanorod networks were synthesized through the direct evaporation of metal zinc with high purity via a chymical evaporation deposition (CVD) method in Ar and O2 at 910 °C without any catalyst. The nanorod networks of as-synthesized ZnO were characterized using scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM), and X-ray diffraction (XRD). The branches within one network show very regular orientation relationships: either perpendicular or parallel to each other. The nanorods follow a growth direction . Photoluminescence (PL) spectroscopy were measured at room temperature and showed the different PL features of other nanostructures. Two typical emission peaks at -401 nm and at 452-495 nm were observed. Specially, the emission peak at 452-495 nm includes four subordinate peaks.