The current study is designed to evaluate the cardiorenal protective efficacy of the Biochanin-A (BCA) against high-fat-diet (HFD) and streptozotocin (STZ)-induced diabetes in rats. BCA (10mg/kg body weight) was administered to the diabetic rats for a period of 30 days and evaluated its effect on hyperglycemic markers, formation of lipid peroxidation, nitric oxide production and antioxidant enzymes such as superoxide dismutase, catalase and glutathione mediated enzymes. Further, we assessed the impact of BCA on nuclear factor erythroid 2-related factor-2 (Nrf-2) and heme oxygenase-1 (HO-1) along with antioxidant enzymes mRNA expressions by RT-PCR. BCA administration to diabetic rats resulted in attenuation of hyperglycemia and oxidative stress in both the kidney and heart. Further, BCA enhanced the endogenous antioxidant activities in the kidney and heart and up-regulated their corresponding mRNA expressions. In addition, BCA treatment produced notable up-regulation of Nrf-2 and HO-1 mRNA expressions in the cardiac and renal tissue of diabetic rats. In conclusion, the current study revealed that BCA could protect from diabetes-induced complications such as cardiomyopathy and nephropathy by activating the Nrf-2/HO-1 pathway and enhancing the endogenous antioxidant state in the kidney and heart.