Diabetes is one of the most common chronic disease in the present world. Socio-economic growth and industrialization are rapidly occurring in India,the urban-rural divide in prevalence is narrowing as urbanization is spreading widely, adversely affecting the lifestyle of populations. Indians have a greater ethnic and genetic predisposition to diabetes so the younger people are also affected with diabetes. The burden of the disease is increasing and it is a costly disease for developing countries. A study by diabetic research and clinical practice 2010, by 2030 there will be nearly 87 million diabetics in India. This is a serious condition. This article explains the role of glucose in the body, entry of glucose, role of insulin and the increasing prevalence of diabetes in India.