In the present work, undoped, (Cu, In) doped and co-doped ZnO nanoparticles are successfully prepared by co‐precipitation technique. The molar concentrations of dopant elements are 2% for both Cu and In doping, and 1%–1% for the Cu/In co-doping. Energy dispersive X-ray (EDX) analysis confirms the chemical composition of the prepared nanoparticles, and proves the effective introduction of dopant elements into the ZnO host lattice. The X-ray diffraction (XRD) analysis indicates the formation of single-phase hexagonal wurtzite structure for the all synthesized samples. The morphological investigation shows change of ZnO nanoparticles from nanotubes to spherical shape under the effect of doping and co-doping. The reflectance spectra show red shift of the absorption edge as a result of Cu doping and Cu/In co-doping effect. The PL spectra confirm emission bands in the visible rage related to the presence of defects, such as oxygen vacancies, as well as shallow trap levels near the conduction band edge. These oxygen deficiencies have an important effect on the charge carrier transport, resulting in the enhancement of electrical conductivity in doped and co-doped ZnO. In addition, photocatalytic performance experiments prove that the photocatalytic activity of ZnO, in the degradation of amido black 10B dye, is significantly enhanced via (Cu, In) doping and co-doping.