Recently, in particular, environmental contaminants have continued to be the most potential cause of many diseases, those of toxic metals which are capable of accumulating within vital organs of both humans and animals, inducing reactive oxygen species (ROS) production and causing severe health hazards within biological systems. Nickel (Ni) and chromium (Cr) are toxic elements producing highly reactive radicals which are able to disable enzymatic antioxidants through binding to their active sites. The present study has been designed to evaluate the protective role of curcumin against testicular dysfunction induced by nickel-chromium combination. The concentrations of Ni and Cr as well as the activities of antioxidants endogenous enzymes including; glutathione peroxidase (Gpx), glutathione reductase (GR), catalase (CAT), and superoxide dismutase (SOD) were all determined in the testicular tissue while hematological biomarkers were being measured in the blood of experimental rats. Mixture metals resulted in significant variances within testicular tissues. However, oral administration of curcumin provided a significantly protective role against combined toxicity of nickel-chromium and reduced histopathological alterations due to antioxidant property represented in scavenging and chelating properties as concluded from the present investigations.