The term diabetes mellitus describes a metabolic disorder of multiple aetiology characterized by chronic hyperglycemia with disturbances of carbohydrate, protein and fat metabolism resulting from defects in insulin secretion, insulin action or both. It is a leading public healthcare problem with increasing incidence and long term complications of various organs such as kidney, neuron, eye, heart. These complications are mainly a consequence of macro and micro vascular damages of the target organs and also associated with ongoing malfunction of them . The prevalence of diabetes is increasing world-wide. It is surprising that there is no age limitation for presentation of type 2 diabetes. I think the study will help to create awareness among the physicians and also the diabetic patients regarding the damaging effect of diabetes on lung functions. This may also help earlier diagnosis and proper management of pulmonary complications in this group of patients. The peoples also be aware of silent killing effect of diabetes.