Renal ischemia results in tissue injury and is complicated by the fact that reperfusion although essential for the survival of ischemic renal tissue, causes additional damage. Ischemia-reperfusion injury is a serious complication in organ transplantation. Formation of reactive species has been implicated as the causative factors of these injuries. The present study was designed to investigate the effect of Mn (III) tetrakis (4-benzoic acid) porphyrin (MnTBAP), a broad spectrum reactive species scavenger in prevention of renal ischemia-reperfusion (IR) injury in rats. In this study, four groups of male rats consisting of sham-operated, sham-MnTBAP, ischemia-reperfusion (IR) and IR-MnTBAP were used. Anaesthetized rats were subjected to bilateral renal artery occlusion for 40 min followed by reperfusion for 6 hours. Rats were administered either MnTBAP (10 mg/kg IV bolus 15 min prior to IR) or saline. In all of the animal groups, mean arterial pressure and heart rate were recorded for the duration of the experiment by AD instruments (powerlab). Renal function was assessed by serum creatinine (SCr), BUN, fractional excretion of Na+ (FENa), urinary N-acetyl-ß-D-glucosaminidase (NAG) and serum aspartate aminotransferase (AST) measurements. We found that MnTBAP significantly reduced the IR mediated increases in SCr, BUN, FENa, AST and NAG. These results suggest that MnTBAP reduce the renal dysfunction and injury associated with renal IR.