Aim To study the effect of 2,3-dioxoindoline on experimental atherosclerosis in quail and its possible mechanisms. Methods Atherosclerosis model in quail was established and divided randomly as group of 2,3-dioxoindoline(20,60,120 mg/kg),lovastatin(79.5 mg/kg),model and control.The lipid levels in serum were detected at the end of 5th and 8th week respectively.The aorta,myocardium and liver were examined histopathologically and so were the level of total superoxide dismutase(SOD),glutathione peroxidase(GSH-Px) and total antioxidant capacit(T-AOC) while reduced malondiadehyde(MDA) in serum at the end of 8th week. Results At the eighth weekend compared with model group,2,3-dioxoindoline decreased the levels of total cho-lesterol(TC)(p<0.01),triglyceride(TG)(p<0.01),low density lipoprotein cholesterol(LDLC) and apolipoprotein B(p<0.05,p<0.01),increased high density lipoprotein cholesterol(HDLC) and apolipoprotein A in serum.At the same time,TC and TG in the liver,myocardial and aortic wall were reduced(p<0.05,p<0.01),the degree of atherosclerotic lesion in aorta and coronary artery and fatty degeneration of liver in 2,3-dioxoindoline group was reduced(p<0.05,p<0.01),the level of the serum SOD,GSH-Px and T-AOC was increased while MDA level was reduced(p<0.05,p<0.01). Conclusions Beforehand administration of 2,3-dioxoindoline can inhibit atherosclerotic lesion probably due to decreasing blood lipid level and antioxidation.