Background and Objective: Clinically significant changes in central nervous system (CNS) function are observed following brief periods of CNS blood flow interruption. Stroke patients exhibit cognitive, emotional, and electrophysiological changes during the recovery phase. Lavender belongs to the Labiatae family and is used for a variety of cosmetic and therapeutic purposes in herbal medicine. This study investigates the effect of ethanolic extract of lavender on cerebral edema in a rat stroke model. Materials and Methods: Lavender extract was injected intraperitoneally (100 mg/kg and 200 mg/kg) for 20 consecutive days. 2 hours after the last dose cerebral artery ligation surgery was performed. 24 hours after the induction of ischemia, cerebral edema was assessed. Also, antioxidant capacities of plasma and brain tissue were assessed in the intact groups. Results: This study shows that treatment of rats with ethanolic extract of lavender caused a significant decrease in brain water content compared with ischemia group. Lavender extracts increased antioxidant capacity in serum and brain tissue in the intacts compared with the control group. Conclusion: The results indicated that lavender extract has neuroprotective activity against cerebral ischemia and the mechanism may be related to augmentation in endogenous antioxidant defense and inhibiting oxidative stress in the rat brain. References 1- Bhuiyan MIH, Kim YJ. Mechanisms and prospects of ischemic tolerance induced by cerebral preconditioning. International Neurourology Journal. 2010 14: 203. 2- Lakhan SE, Kirchgessner A, Hofer M. Inflammatory mechanisms in ischemic stroke: therapeutic approaches. J Transl Med. 2009 7: 97. 3- Warner DS, Sheng H, Batinić-Haberle I. Oxidants, antioxidants and the ischemic brain. J Exp Biol. 2004 207: 3221. 4- Crack PJ, Taylor JM. 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