Objective: To investigate cardiovascular risk factors in women with polycystic ovary syndrome (PCOS) combined with subclinical hypothyroidism (SCH). Patients: A place-controlled study was performed. Group 1: 29 patients with PCOS and SCH; Group II: 35 patients with PCOS and normal thyroid function; and Group III: 34 healthy women with normal thyroid function. Main measure indexes: Total cholesterol (TC), triglyceride (TG), low-density lipoprotein (LDL) and high-density lipoprotein (HDL), Carotid Arterial Intima-Media Thickness (CIMT), free triiodothyronine 3 (FT3), free triiodothyronine 4 (FT4), thyroid stimulating hormone (TSH), fasting glucose, 1-hour oral glucose tolerance test (OGTT1), 2-hour oral glucose tolerance test (OGTT2), fasting insulin, insulin after 1 hour oral glucose (INS1), insulin after 2 h oral glucose (INS2), HOM-IR ¼ (fasting glucose fasting insulin)/22.5. Results: TG, TC FIN, INS1, and HOM-IR levels were significantly higher, but the mean HDL level was significantly lower in Group I than in Group II (p50.05). LDL cholesterol, FGOGTT1, OGTT2, and insulin after 2 h oral glucose were not significantly higher in Group I than in Group II (p40.05). TG, TC, FIN and INS contents 2 h meal, HOM-IR levels were significantly higher, and the mean HDL cholesterol level was significantly lower in Group I than in Group III (p50.05). Blood glucose levels after 1 and 2 h were not significantly higher in Group I than in the Group III (p40.05). Carotid Arterial Intima-Media Thickness (CIMT) was significantly thicker in Group I than other two groups. Conclusions: The PCOS patients combined with SCH have higher risk of cardiovascular risk factors than in controls or in patients with PCOS.