Type 2 diabetes mellitus and thyroid diseases are the two most common endocrine disorders encountered in India. Aim is to assess the thyroid function tests in diabetes mellitus patients and normal healthy volunteers. Comparative study was done on 30 diabetes mellitus patients as cases and 30 normal healthy volunteers as controls.Mean and S.D. of thyroid stimulating hormone (TSH) was significantly higher in the diabetes mellitus group (5.30± 3.24 mIU/dl), when compared to control group (2.72±1.22 mIU/dl). The results also showed elevated total cholesterol, low density lipoprotein (LDL) in diabetes mellitus group, when compared to control group.If the diabetes mellitus patients remain undiagnosed for subclinical hypothyroidism, it can aggravate the risk factors like hypertension and dyslipidemia and can lead to an increased cardiovascular risk in these patients. Thus routine assessment of thyroid hormone level in the early stage of diabetes mellitus will help in the managementof diabetes mellitus patients.