Diabetes and thyroid dysfunction are the two most common endocrine disorders worldwide. Studies have shown that diabetes and thyroid dysfunction mutually influence each other and are associated with each other frequently. Subjects with diabetes have been found to have higher prevalence of thyroid dysfunction compared to the general population. But, the prevalence of thyroid dysfunction in subjects with diabetes has been found to differ widely between different studies. The reported prevalence of thyroid dysfunction is 10-24% in subjects with diabetes, while it is around 6-13% in subjects without diabetes. Studies have shown that thyroid dysfunction is more common in women with diabetes. A recent meta-analysis revealed a mean frequency of thyroid dysfunction of 11% in diabetes. Hence based on above findings the present study was planned for Clinical Evaluation of Prevalence of the thyroid disorders in Patients Diagnosed with the Type 2 Diabetes Mellitus in Bihar Region. The present study was planned in Department of Internal Medicine, Jawaharlal Nehru Medical College and Hospital, Bhagalpur, Bihar, India. In the present study 50 cases of diabetic patients were enrolled and evaluated. Diabetes was defined as per the American Diabetes Association criteria (Fasting plasma sugar ≥126 mg/dl, postprandial blood sugar ≥200 or Glycated hemoglobulin [HBA1c] ≥6.5% on 2 occasions). All the subjects underwent clinical and laboratory assessment. The demographic data included information regarding age, duration of diabetes, co-morbidities like hypertension, dyslipidemia, etc and presence of complications of diabetes. BMI was calculated using the height and weight of the subjects. The data generated from the present study concluded that prevalence of thyroid dysfunction is significantly high in the studied subpopulation with type 2 diabetes. The most common abnormality is subclinical hypothyroidism and autoimmunity is the cause of thyroid dysfunction in large proportion of these subjects. Thyroid autoimmunity is common even in euthyroid subjects. The findings of this study indicate that screening for thyroid disease among patients with diabetes should be routinely performed to be able to identify thyroid autoimmunity and diagnose subclinical hypothyroidism early.