In an attempt to find the activity of Aster glehni (Compositae) leaves on the obesity in vivo, 30% ethanolic extract rich in caffeoylquinic acids was orally treated with 100 and 200 mg/kg for consecutive four weeks during feeding high-fat diet in rats for 6 weeks. This extract prevented the increase of atherogenic index and body weight and oxidative stress from dietinduced obese rats probably due to the pharmacological mechanism of the CQ complex.