Purpose of this study is to determine the influence of insulin resistance on total renin with polycystic ovary syndrome (PCOS). Clinical, ultrasonographic and hormonal findings were used to define PCOS. Insulin resistance was estimated by the continuous infusion of glucose with model assessment (CIGMA) in early follicular phase. The sensitivity and specificity of the serum total renin level to diagnose women with PCOS were calculated as 80% and 71.4%, respectively. Serum total renin level which is independent from insulin resistance can be used as a diagnostic marker in normotensive women with PCOS.