Diabetes Mellitus is a clinical syndrome characterized by hyperglycemia caused by absolute or relative deficiency of insulin. Lack of insulin affects the metabolism of carbohydrate, protein and fat and can cause significant decrease of water and electrolytes homeostasis Various thyroid abnormalities may co-exist and interact with diabetes mellitus. Diabetes mellitus affects thyroid functions at many sites, from hypothalamic control of thyroid stimulating hormone (TSH), release to T3 production from T4 in the target tissues. The study was carried out in Department Of Medicine, Pandit Deendayal Upadhyaya Medical College, Churu, Rajasthan, from 11 Oct. 2017 to 10 Oct. 2018 for a period of one year. It was a hospital based cross sectional observational study. We have selected 120 cases (60 males and 60 females) of T2DM following the inclusion and exclusion criteria of our study protocol from medicine ward. Serum glucose was estimated by GOD-POD method. Serum HBA1c was measured by HPLC, and thyroid hormones were measured by ECL technology. It was a hospital based cross sectional observational study.It was observed that high incidence of abnormal thyroid hormone levels were seen among T2DM subjects. Out of all patients having thyroid dysfunction, maximum number of T2DM patients had subclinical hypothyroidism.