Diabetes mellitus has now assumed epidemic proportions in many countries of the world. With the present population of 19.4 million diabetics, and approximately 60 million by the year 2025, India would rank first in its share of the global burden of diabetes. The autonomic nervous system (ANS) is an extensive neural network whose main role is to regulate the milieu intérieur by controlling homeostasis and visceral functions. Diabetes mellitus is most commonly associated with autonomic dysfunction, in persons with diabetes; prolonged hyperglycemia leads to degradation of the microvasculature, leading to a specific form of autonomic dysfunction firmed “Diabetes Autonomic Neuropathy”. The diagnosis of Autonomic Neuropathy is often difficult to establish in individuals, since clinical symptoms generally appear late in the course of the disease and may be nonspecific, Early detection of Autonomic Neuropathy would suggest the need for an aggressive approach in the management of diabetes mellitus with the help of simple autonomic function test.