Diabetes mellitus is a disease that affects many metabolic pathways. It is associated with insulin resistance, impaired insulin signaling, β-cell dysfunction, abnormal glucose levels, altered lipid metabolism, sub-clinical inflammation, and increased oxidative stress. The present study aimed to explore the role of catechin in the treatment of Diabetes mellitus. Catechins are polyphenolic compounds or flavanols of the flavonoid family found in a variety of plants. Catechins and their antioxidant activity, and the mechanisms of action involved in the prevention of oxidative stresscaused diseases such as cancer, cardiovascular diseases, and neurodegenerative diseases. Insulin resistance in patients with diabetes mellitus causes complications such as cardiovascular and renal diseases. Studies have shown that catechins can be effective in controlling hyperglycemia and preventing the complications of diabetes by improving insulin sensitivity and reducing the risk factors for Type 2 Diabetes Mellitus such as oxidative stress, dyslipidemia, and obesity. Nowadays, diabetes and diabetes-mediated dysfunctions are overwhelming at every corner of the world which has been a sober concern to the current health care professionals. The benefit of catechin consumption still requires confirmation. So, in the present study, an attempt was made to review the use of catechin in diabetes mellitus.