Medicinal plants play pivotal role in preventing various disease. Hyper lipidemia is a major contributor to pathogenesis of cardiovascular diseases and diabetes mellitus. Portulaca oleracea Linn belonging to the family Portulacaceae. P oleracea is an herbaceous weed with many pharmacological activities like anti inflammatory, antibacterial, antiplasmodial activity. Objective: The present study is an attempt to investigate its antihyperlipidemic activity as mentioned in siddha literature. Methods: Administration of dexamethasone was given (10 mg/kg.S.C) to the adult wister rats for 8 days induces hyperlipidimea characterized by marked increase in serum cholesterol and triglyceride levels along with increase in atherogenic index. Result: The Ethanolic extract of leaves of Portulaca oleracea Linn. (200 and 400 mg/kg) treatment has showed significant inhibition against dexamethasone induced hyperlipidemia in rats by maintaining the serum levels of cholesterol, triglycerides and near to the normal levels. © 2012 Elsevier B.V., All rights reserved.