Introduction: Polycystic ovary syndrome (PCOS) is the most common endocrinological disorder in women of reproductive age group. It is the leading cause of infertility in females presenting a wide range of clinical manifestations. Aim: To investigate the glycaemic status, calcium, phosphorus, insulin and 25OH vitamin D levels in women with polycystic ovary syndrome and to compare these parameters with age and BMI matched healthy control women. To find out the correlation between insulin resistance and vitamin D among PCOS women. Materials and Methods: The study comprised of 80 newly diagnosed polycystic ovary syndrome women in the age range of 23 to 33 years. The biochemical parameters measured in the study includes fasting blood sugar, fasting insulin, calcium, phosphorus and vitamin D. The values obtained were compared with equal number of age and body mass indexed (BMI) matched healthy controls. Results and Discussion: In the present study the levels of fasting glucose, fasting insulin were increased, whereas serum calcium and 25 – OH vitamin D levels were decreased in PCOS women when compared with healthy controls. Though serum phosphorous levels appear to be decreased in PCOS women, it is not statistically significant when compared to controls. Conclusion: A high prevalence of vitamin D deficiency and low calcium levels were observed in PCOS women from our population when compared to controls. Insulin resistance was predominantly seen in PCOS subjects when compared with controls, indicating the association of vitamin D levels with insulin resistance.