The objective of this study was to evaluate the renoprotective effects of Uncaria Tomentosa (cat's claw) on ischemic acute kidney injury induced by renal clamping in rats. The hypoxia and hypoperfusion increase the production of reactive species already present in the inflammatory process. Results showed that the renal function evaluated by creatinine clearance, the urinary excretion of peroxides and malondealdehyde indexes demonstrated that UT induced renoprotection, probably related to its antioxidant activities.