Heterogeneous Polycystic ovary syndrome (PCOS) is a low grade inflammatory diseases common with many of the young female and strongly associated with peripheral insulin resistance. Our study focused on investigating the effects of interferon gamma (IFN γ) in control of IR in obese PCOS patients with matched control. PCOS patients diagnosed by Rotterdam criteria and BMI matched controls were checked for Fasting insulin and IFNγ, FSH, LH, prolactin, testosterone, triglycerides and glucose levels and IR was calculated by Homeostasis Model Assessment (HOMA-IR), Quantitative Insulin Sensitivity Check Index (QUICKI) and McAuley (McA) index. Fasting glucose, insulin, and IR by QUICKI, HOMA-IR and McA is higher in obese PCOS in compared to control. High serum testosterone, LH, and FSH levels were also observed in women with PCOS. But IFNγ is not statistically significant and not correlated significantly with fasting insulin (ρ = -0.004), HOMA-IR (ρ = -0.02), QUICKI (ρ = -0.11) or McA (ρ = -0.15) in obese women with PCOS. We suggest that development of peripheral insulin resistance in PCOS is not through the mediation of IFNγ. Further studies are needed to prove the suggested mechanism and to develop drugs for reversing PCOS pathology.