Polycystic ovary syndrome (PCOS), the most common reproductive endocrine disorder of premenopausal women, is strongly associated with hyperinsulinemia and type 2 diabetes mellitus (T2DM). Given the phenotypic overlap between PCOS and T2DM, our objective was to investigate whether the TCF7L2 rs7903146(C/T) and the KCNJ11 E23K variants are involved in susceptibility to PCOS and related traits in a Greek population. A total of 183 PCOS patients and 148 healthy controls participated. All participants were Greeks. Blood was taken before hormonal therapy. PCOS patients and healthy controls were genotyped for the TCF7L2 and KCNJ11 variants. The T allele of the TCF7L2 rs7903146 variant was found to be marginally over-represented in Greek patients with PCOS. There was no association between KCNJ11 E23K polymorphism and PCOS in the present study. In addition, there were no associations observed between hormone levels and insulin resistance in PCOS carriers of TCF7L2 rs7903146 and KCNJ11 E23K variants. These data provide evidence that the rs7903146 variant of the TCF7L2 gene might influence PCOS predisposition, while no association is observed between the E23K variant of KCNJ11 and susceptibility to PCOS and related traits.