Dyslipidemia is a very common metabolic abnormality in women with polycystic ovary syndrome (PCOS). Insulin resistance is a key pathophysiology of PCOS, thus dyslipidemia in women with PCOS may be consistent with those found in an insulin resistant state. In recent meta-analysis, triglycerides and low-density lipoprotein (LDL) cholesterol levels were 26 mg/dL and 12 mg/dL higher, and high-density lipoprotein cholesterol concentration was 6 mg/dL lower in women with PCOS than those of controls. Alterations in LDL quality also have been reported in women with PCOS: women with PCOS have an increased proportion of atherogenic small dense LDL or decreased mean LDL particle size. However, in a recent Korean study, non-obese Korean women with PCOS had no significant quantitative or qualitative changes in LDL cholesterol profile. Lipoprotein (a) has been identified as an independent risk factor for coronary heart disease, and its elevation in PCOS patients has been consistently reported in diverse studies including non-obese Korean population. Some studies have investigated apolipoprotein (Apo) A-I and ApoC-I levels in women with PCOS and levels of ApoA-I, which has cardio-protective effects, were significantly lower in women with PCOS than those of controls. ApoC-I is known to increase the postprandial serum lipid level that is common in coronary artery disease patients, and one study reported that such an elevation may be the earliest variation of lipid abnormality in women with PCOS. In conclusion, women with PCOS should receive a complete lipid test, and lifestyle modification, including diet and exercise, is the first line therapy for all women with PCOS and is particularly important for those with dyslipidemia.