Diabetes mellitus on pulmonary symptoms are poorly described. Some authors report normal pulmonary functions and have conducted that spirometer is not at all important in patients with diabetes. The problems which are connected with Diabetes mellitus are often induced by macro vascular and micro vascular damages. This case control study performed with 50 type 2 diabetes patients and 50 non-diabetic patients. Cases and controls were chosen by implementing inclusion & exclusion criteria using random sampling process. The study was undertaken to evaluate whether the duration of diabetes has any association with severity of pulmonary functions. Mean of the anthropometric parameters and age in diabetic and control group were compared with no significant difference (p value>0.05) between the two groups. In our study we conclude that with increase in duration there was reduction in pulmonary parameters.