Background: PCOS, or polycystic ovarian syndrome, is the most prevalent endocrine condition, which affects women in their reproductive years and has a 6–10% frequency in the general population. The present study was conducted to assess role of vitamin d supplementation among PCOS women with vitamin D deficiency. Materials & Methods:94 women diagnosed with PCOS with Vitamin Ddeficiency were divided in to two groups of 47 women in each group. Group I women were given treatment with Metformin &calcium 1000mg daily along with Vitamin D3 60K IU weekly for 6weeks followed by monthly for 4 months. Group II women were given treatment with Metformin 1000mg daily only. Menstrual cycles, hyperandrogenic symptoms like hirsutism & acne, history of features of PCOS was done before starting treatment. Results: age group 16-20 years comprised of 4 patients and 7 patients, 21-25 years had 18 and 17, 26-30 years had 20 and 16 and 31-35 years had 5 and 7 patients in group I and II respectively. The difference was non- significant (P>0.05). Vitamin D (ng/ml) before treatment was 12.1 and 13.2 and after treatment was 12.9 and 13.8 in group I and II respectively. BMI (Kg/m2) before treatment was 26.4 and 25.1 and after treatment was 24.2 and 24.7 in group I and II respectively. Waist hip ratio before treatment was 0.84 and 0.83 and after treatment was 0.82 and 0.81 in group I and II respectively. Hirsutism before treatment was 13.7 and 13.5 and after treatment was 9.7 and 11.4 in group I and II respectively. Ovarian volume (cm3) before treatment was 8.9 and 8.5 and after treatment was 6.3 and 7.2 in group I and II respectively. The difference was non- significant (P> 0.05). Conclusion: Calcium and vitamin D are safe medications with few side effects; thus it is advised for ladies, particularly those who are deficient in vitamin D.