The National Institute of Health (NIH) criteria include clinical and/or biochemical hyperandrogenism and chronic anovulation for diagnosing PCOS whereas the most recent androgen excess and PCOS (AE–PCOS) Society criteria recommend that PCOS should be defined as clinical or biochemical hyperandrogenism associated with ovulatory dysfunction in the form of oligo-anovulation or polycystic ovaries on ultrasound. Insulin resistance and hyperandrogenism is found to play a key role in the pathogenesis of polycystic ovarian syndrome. Hence based on above findings the present study was planned for Clinical Assessment of anovulatory infertile women with PCOS by Comparative Administration of N-Acetyl Cysteine with Metformin. The present study was planned in Department of Obstetrics & Gynaecology, Government Medical College, Bettiah, West Champaran, Bihar, India. The 50 females diagnosed with the polycystic ovarian syndrome (PCOS) were enrolled in the present study. The 25 females were administered with the Metformin and 25 females were administered with the N- Acetyl cysteine (NAC). The data generated from the present study concludes that NAC improves the clinical features, biochemical markers of insulin resistance, hormonal levels, anovulation and consequently the long-term health status of women with PCOS through inhibition of oxidative stress and improvement of peripheral insulin more effectively when compared with metformin. Due to the lack of adverse effects, NAC can be regarded as an appropriate substitute for insulin-reducing medications in the treatment of PCOS patients.