Doped ZnO nanorods with different magnesium (Mg) concentrations have been successfully fabricated on Si (1 1 1) substrates via two-step method. The influence on the nanorods morphologies and crystallinities of the Mg concentrations was characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD) and photoluminescence (PL) spectra. The SEM results show that it is beneficial to grow regular ZnMgO nanorods with the increase of Mg concentrations, and the XRD results indicate that the nanorods possess the preferential orientation along the c-axis when the molar ratio of Mg/Zn is 0.5, which possess the best crystalline. The photoluminescence (PL) spectra show that the UV emissions have the obvious blue shift with the increase of Mg concentrations. ZnMgO has a wider bandwidth with increase in Mgcontent. (C) 2014 Elsevier B.V. All rights reserved.