In this study we investigated the hypolipidemic and anti-lipoprotein-oxidation activities of phenolic extract from sweet basil a popular culinary herb. The hypolipidemic activity was studied in mice model injected intraperitoneally with Triton WR-1339 at a dose of 200mg/kg body weight. The animals were grouped as follows: normolipidemic control group (n=8), hyperlipidemic control group (n=8) and phenolic extract-treated group (n=8) at a dose of 200mg/kg body weight. After 7h and 24h treatment, the oral administration of the phenolic extract exerts a significant reduction of plasma total cholesterol, triglycerides and LDL-cholesterol concentrations (P<0.001). On the other hand, we demonstrated that the phenolic extract prevents plasma lipid oxidation by 16% (P<0.001), 20% (P<0.001), 32% (P<0.001) and 44% (P<0.001) at a doses of 10, 25, 50 and 100μg/mL, respectively. The results were compared with ascorbic acid used as standard synthetic antioxidant. HPLC analysis shows that the extract contains 4 major phenolics and is especially rich in rosmarinic acid. This finding indicates that the phenolic extract might be beneficial in lowering hyperlipidemia and preventing atherosclerosis.