Background and Aims: Type 2 diabetes mellitus (T2DM) during the chronic stage elicits significant micro and macrovascular complication and imposes mortality and morbidity among the individuals. However, the effect of T2DM on the lung as a target end organ damage was not widely studied. Hence, the present study was done for the spirometry analysis of pulmonary functions in T2DM patients. Methods: This was a cross-sectional study conducted on 50 T2DM patients and they were subjected to spirometry evaluation. The restrictive pattern of lung functions was analyzed by evaluating the following parameters forced vital capacity (FVC) in liters, forced expiratory volume in 1 second (FEV1), and FEV1/FVC were evaluated. The association between lung function parameters and duration of diabetes, glycated hemoglobin (HbA1c) were also analyzed. Results: In this study among the diabetic patients, the mean FVC was 2.45±0.36 L, the mean FEVI was 1.82±0.12 (L/s) and the mean FEV1/FVC was 87.42±7.54, respectively. Regarding lung complication, out of 50 diabetic patients, 25 (50%) had normal lung functions, 16 (32%) had mild restriction and 9 (18%) had moderate restriction. The FVC, FEVI, and FEV1/FVC were significantly reduced in diabetic patients with moderate lung restriction as compared to normal and mild restriction patterns. Diabetes duration displayed no significant association with a decline in pulmonary function and FEV1/FVC showed weak significant negative correlation (r=−0.412; p=0.02) with HbA1c levels. Conclusion: The study shows that in diabetics patients there was a marked decline in pulmonary function and it might be due to uncontrolled diabetes-related complications.