Objectives: To determine the correlation of subclinical hypothyroidism (SCH) with polycystic ovarian syndrome (PCOS) and to assess its impact on the clinical, biochemical and hormonal features in polycystic ovarian syndrome. Background: PCOS is one of the most common endocrinopathies seen in women of the reproductive age group with a prevalence ranging from [Formula: see text] to [Formula: see text] globally (Joshi et al., 2014) and [Formula: see text] to [Formula: see text] (Malik et al., 2014) in the Indian population. Thyroid disorders are quite commonly seen in PCOS patients, SCH are seen in up to [Formula: see text] of this population (de Medeiros et al., 2018). Its association with PCOS has been insufficiently explored and therefore this study was designed to better understand the correlation. Methodology: This was a cross-sectional study conducted from November 2019 to 2021 in the Department of Obstetrics and Gynecology of Jawaharlal Nehru Medical College and Hospital, Aligarh, India, on 150 PCOS women in the age bracket of 18–35 years. They were divided in two groups: one with normal thyroid levels and the other with SCH. Measurement of clinical, anthropometrical, biochemical and hormonal profile was made in both groups and comparison was made using appropriately matched tests of significance and coefficient of correlations. Results: Notable findings included a positive and statistically significant correlation between SCH and menstrual cycle irregularities ([Formula: see text], [Formula: see text]), infertility ([Formula: see text], [Formula: see text]), body mass index ([Formula: see text], [Formula: see text]), waist to hip ratio ([Formula: see text], [Formula: see text]), testosterone([Formula: see text], [Formula: see text]), total cholesterol ([Formula: see text], [Formula: see text]), triglyceride values ([Formula: see text], [Formula: see text]), fasting insulin ([Formula: see text], [Formula: see text]) and HOMA-IR ([Formula: see text], [Formula: see text]). A positive but statistically insignificant correlation was found with hirsutism ([Formula: see text], [Formula: see text]), luteinizing hormone ([Formula: see text], [Formula: see text]), follicle-stimulating hormone ([Formula: see text], [Formula: see text]), prolactin levels ([Formula: see text], [Formula: see text]), high-density lipoprotein ([Formula: see text], [Formula: see text]), low-density lipoprotein ([Formula: see text], [Formula: see text]) and fasting blood sugar values ([Formula: see text], [Formula: see text]). No statistical significance with systolic blood pressure ([Formula: see text], [Formula: see text]) and diastolic blood pressure ([Formula: see text], [Formula: see text]) was found. Conclusion: The study showed a significant correlation between SCH and multiple variables in PCOS and thereby necessitating thyroid screen in PCOS population.