Polycystic ovary syndrome (PCOS) is a main cause of women infertility. There are data suggesting an increased risk for cardiovascular disease in PCOS. Insulin resistance might play a role in the pathogenesis of PCOS and its metabolic complications. The aim of the study was to asses the prevalence of The National Cholesterol Education Program (NCEP)-defined metabolic syndrome (MS) in women with PCOS in relation to insulin resistance and endothelial dysfunction soluble E-selectin (sE-selectin) and soluble intercellular cell adhesion molecule-1 (sICAM-1).Euglycemic hyperinsulinemic clamp, serum sE-selectin, sICAM-1, and sex hormones were measured in 97 women with PCOS (33 lean and 64 overweight or obese) and 33 healthy women (22 lean and 11 overweight or obese). MS was present in 21 PCOS patients (21.6%). Both the lean and obese women with PCOS had lower insulin sensitivity (P=0.03 and P=0.01). The PCOS group had significantly higher serum concentrations of sICAM-1 and E-selectin than control group (P=0.008 and P=0.01, respectively). The comparison of the subgroups of patients with PCOS according to the presence of the MS revealed the significantly higher sICAM-1 (P<0.001) and E-selectin (P<0.001) concentration, lower insulin sensitivity (P<0.001), SHBG (P=0.005) and higher free androgen index (FAI) (P=0.018) in patients with PCOS and MS. Analysis of variance showed that together with the increase of the number of NCEP criteria in PCOS group, there was a significant decrease of insulin sensitivity, SHBG and an increase in sICAM-1 and E-selectin serum concentration and FAI (P<0.001). The significant inverse correlations between the insulin sensitivity and sICAM-1 (r=−0.33, P=0.002) and E selectin (r=−0.33, P<0.0001) were observed. Our study indicates that in young PCOS women, insulin resistance is associated with both classical and non-classical risk factors for cardiovascular disease.