Heavy metals are known to accumulate in various vital organs including heart, liver, kidneys etc. and induce generation of free radicals inside animal body. Thus heavy metals cause oxidative damage in tissues like liver, heart and kidneys. The purpose of this study was to investigate the role of tannic acid, a plant polyphenol, against cadmium chloride-induced oxidative stress mediated nephro-toxicity in male rats. The rats of control group were treated orally with normal saline (0.09% NaCl). The rats of second, third, fourth and fifth groups were treated with 0.44mg/ kg body weight cadmium chloride, 12.5 mg/kg bw tanic acid plus 0.44mg/kg body weight cadmium chloride, 25 mg/kg bw tannic acid plus 0.44mg/kg body weight cadmium chloride and 50 mg/kg bw tannic acid plus 0.44mg/kg body weight cadmium chloride, respectively for 14 days. The results indicated that cadmium chloride caused a significant alteration in the level of lipid peroxidation (LPO), protein carbonyl content (PCO), reduced and oxidised glutathione content (GSH and GSSG), total sulfhydryl content (TSH), cytosolic and mitochondrial superoxide dismutase activities (Cu-Zn SOD and Mn SOD), activities of catalase, xanthine oxidase and xanthine dehydrogenase (XO ad XDH) and in the activities of Kreb's cycle as well as respiratory chain enzymes. Pre-treatment of rats with tannic acid at increasing doses ameliorates the changes in a dose-dependent manner and tannic acid at 25 mg/kg bw caused the most significant protection against cadmium induced changes. In addition, the results of histological studies showed that cadmium chloride caused significant damages in the renal tissue morphology of rats and this cadmium induced deteriorative changes were found to be protected in a dose-dependent manner when the rats were pretreated with tannic acid in increasing doses along with cadmium chloride. The results of the current studies raise the possibility using tannic acid as a potent reno-protective agent, in future days, against cadmium-induced damages. © 2015, Global Research Online. All rights reserved.