Plasma high density lipoprotein(HDL) can be oxidized in vitro and in vivo as can low density lipoprotein(LDL), which causes many changes in HDL properties, such as peroxidation of polyunsaturated fatty acids, hydrolysis of phosphatidylcholine, apolipoprotein aggregation or degradation. HDL oxidative modification in vivo might be induced by arterial endothelial cells, macrophages and blood polymorphonuclears, monocytes. Ox-HDL might metabolize through scavenger receptors but not normal HDL receptors. Ox-HDL has many atherogenic roles. Vitamin E, C supplementation can inhibit HDL oxidation and may prevent the atherosclerosis.