A single dose of ruthenium red induces serious functional and structural changes in the liver. However, few data exist with respect to its effects on kidney functionality and oxidative stress status. The time-course of a single intraperitoneal administration of ruthenium red on systemic oxido-reductive status and kidney functionality was assesed in rats. Ruthenium red in aqueous solution was administered intraperitoneally in the dose of 20 mg/kg. Control group was treated with saline solution only. Oxidative stress was assessed by measuring lipid peroxidation products and nitric oxide catabolites. Serum urea and creatinine were measured for determination of renal function. A significant increase in serum ruthenium red was observed at 30 minutes after the administration of ruthenium red and the peak response was detected at 60 minutes and serum ruthenium red decreased slowly afterwards. Creatinine and urea showed significant increases after ruthenium red administration. Lipid peroxidation products in serum and kidney tissue showed significant time-dependent increases after ruthenium red injection. Nitric oxide catabolites also exhibited time-dependent increases after ruthenium red injection.Asingle intraperitoneal injection of rutheniumred caused renal and systemic oxidative stress, and induces nephrotoxicity in rats.