Background and Objective: Atherosclerosis is a diffuse, systemic disease that affects the coronary, cerebral, and peripheral arterial trees. Clopidogrel is widely used antiplatelet agent and its efficacy has been proven in cardiac and extracardiac vascular diseases, but it has several side effects. Therefore we investigated whether Sopunghwalhyeoltang, which is widely used for treating the blood stasis syndrome in traditional medicine, could decrease the side effect of antiplatelets and have a synergic effect. Methods & Materials: Male $ApoE^{(-/-)}$ mice were randomly divided into three different experimental groups, non-treated group (Control group), clopidogrel-treated group (CP group) and clopidogrel with Sopunghwalhyeol-tang treated group (CPS group). The control group was fed with only an atherogenic diet, the CP group an atherogenic diet plus clopidogrel 25mg/kg and the CPS group an atherogenic diet plus clopidogrel 25mg/kg with Sopunghwalhyeol-tang 100 mg/kg. We investigated plasma lipids with liver function test, and performed a histological investigation of liver and abdominal aorta. Results: 1. Photomicrographs of liver and abdominal aorta tissue showed lower histological injury and lipid accumulation in the CP and CPS groups than those in the Control group. 2. In the CPS group, plasma triglyceride level was significantly lower than in the Control and CP groups. 3. In the CPS group, the plasma aspartate aminotransferase (AST) level was significantly lower than in the CP group. Conclusions: The above results shows that a combined treatment of Sopunghwalhyeol-tang and clopidogrel have a synergic effect through inhibiting vessel injury and decrease the side effects of clopidogrel alone.