The increasing role of copper oxide nanoparticles (CuO NPs) in many industries and their broad range of applications increase its potential toxic effects. Curcumin possesses a wide range of health benefits. This study aimed to evaluate the role of curcumin in attenuating CuO NPs toxicity in rat kidney. Thirty six animals were divided into five groups; control groups (I, II), curcumin group orally received curcumin 200 mg/kg bw, CuO NPs group orally gavaged 250 mg/kg bw CuO NPs and combined group orally gavaged curcumin and CuO NPs. Treatment was given for 3 months. Administration of CuO NPs revealed elevation in serum creatinine and blood urea nitrogen levels, elevated kidney and urine levels of kidney injury molecule-1, decreased catalase, superoxide dismutase activities, total sulfhydryl, reduced glutathione content, increased serum reactive oxygen species, tissue total oxidant status, lipid hydroperoxides, protein carbonyl, malondialdehyde, nitric oxide levels, increased interleukin-1ÎČ, tumor necrosis factor-α, nuclear factor (NF-ÎșB), and decreased heme oxygenase-1 (HO-1) and Îł-glutamylcysteine synthetase (Îł-GCS) genes expression. Moreover, histopathological alteration in kidney structure was detected. Immunohistochemical-stained sections by caspase-3 reaction revealed apoptosis. Pretreatment with curcumin improved most of the adverse effects in rats treated with CuO NPs regarding oxidative stress and inflammatory indices in kidney, and kept histopathological-and immunohistochemicalstained sections near to normal. This study shows that curcumin administration attenuates the toxicity in the kidney of CuO NPs-treated rats through its antioxidant, anti-inflammatory, and antiapoptotic effects.