Background: Polycystic Ovary Syndrome (PCOS), common cause of ovarian dysfunction. Vitamin D plays a physiologic role in reproduction including ovarian follicular development and luteinisation and its role in PCOS is not very clear. Aim and Objective: To analyse the serum levels of vitamin D among patients with PCOS and healthy controls. Materials and Methods: This cross-sectional study recruited 120 participants with PCOS and 120 healthy controls. After assessing the socio-demographic characteristics of the patients and their control, blood samples were drawn to carry out routine biochemical investigations and serum vitamin D. Results: Mean serum vitamin D levels in study group were lower as compared to controls. Vitamin D deficiency was present in 95.8% of women in study group and 85% of women in control group. Conclusion: Finding of lower vitamin D levels in PCOS women lends support to possible role of vitamin D in pathogenesis of PCOS. Screening for vitamin D deficiency in women with PCOS may provide better insight of its role in PCOS.