It is estimated that 5-7% of women of reproductive age have polycystic ovary syndrome (PCOS). Chronic anovulation, hyperandrogenism, and insulin resistance (IR) are the main characters of this complex syndrome. IR, diabetes and obesity are all strongly correlated with PCOS; moreover, the possibility of direct androgen mediated renin-angiotensin system (RAS) stimulation in women with PCOS is also reported. The aim of the present study was to investigate the correlation between RAS, IR and PCOS.