Background: Polycystic ovarian syndrome (PCOS) and hypovitaminosis D are two most common endocrine disorders in young women leading to many adverse metabolic consequences. Objective of this study was to compare Vitamin D (VD) levels, Body Mass Index (BMI), lipid profile, hormonal parameters, and oocytes in PCOS and non-PCOS infertile females and to explore any association of VD levels with these parameters. Methods: This cross-sectional study was conducted from July 2019 to June 2020 after ethical approval at Aga Khan University in collaboration with Australian Concept of Infertility Medical Centre (ACIMC). It was conducted on 88 infertile females with age range 25–45 years recruited for Intracytoplasmic Sperm Injection (ICSI). Subjects were divided into two groups; PCOS (n=37) and non-PCOS (n=51) based on diagnostic criteria of PCOS. Serum VD was analyzed using ELISA. Statistical analysis was performed on SPSS-20. Mann-Whitney U-test and Spearman’s rank correlation were applied. Results: The mean BMI was significantly higher among PCOS as compared to non-PCOS women (p<0.001). There were statistically significant differences in total cholesterol, triglycerides, Low Density Lipoprotein (LDL-C), High Density Lipoprotein (HDL-C), and Very Low Density Lipoprotein (VLDL) among groups (p<0.05). There was significant correlation of vitamin D with maturity of oocytes (r=0.836, p<0.0001). Conclusion: The findings indicated that PCOs women were obese, had abnormal lipid profile with low VD levels. Low levels of VD were associated with poor maturity of oocytes which is required for successful conception. Pak J Pysiol 2023;19(2):15–9