Mn and Cu co-doped ZnO (Zn0.99-xMnxCu0.01O) nanorods were synthesized by the hydrothermal method. The stoichiometry was provided for increasing x values (0.00, 0.02, and 0.04). The structural analysis was provided by the X-ray diffraction method and found single phases for all Mn/Cu co-doped ZnO nanorods. The surface morphology, size, and shapes of the nanorods were found by the Scanning Electron Microscope (SEM) technique. The elemental compositions of the nanorods were studied by electron dispersive spectroscopy (EDS). Hexagonal Wurtzite structure was proved by c/a ratios of the ZnMnCuO nanorods. The Fourier transform infrared (FTIR) studies were performed and detailed. We successfully produced the ZnO nanorods by multiple doping with Mn and Cu using the hydrothermal. By means of optical measurements, energy band gaps of the samples were calculated and the effects of dopants elements on optical properties were discussed. The refractive index was calculated by using different models. It was found that the refractive index strongly depends on the Mn/Cu co-doped concentration. The photocatalytic activity of Zn0.99-xMnxCu0.01O nanorods was investigated using Methylene Blue (MeB) as model organic dye under ambient visible light. (C) 2020 Elsevier B.V. All rights reserved.