In India, due to smoking, environmental pollution, use of bio mass as a fuel in rural areas etc, there is increase in incidence of pulmonary disorders. Hence, a review of pulmonary function tests is needed. This study has therefore been carried out to reassess the pulmonary function values in normal, Indian population and to check their variations in various obstructive and restrictive pulmonary disorders. Forced spirometry is one of the best test for assessing pulmonary disorders. This simple test provides written record of forced vital capacity (FVC), % forced expiratory volume in 1st second (FEV1%) and peak expiratory flow rate (PEFR). Method: Ours is a cross sectional, comparative study in which we measured FVC, FEV1% and PEFR in 30 normal subjects with the help of computerized spirometer. We also measured the same values in patients of pulmonary disorders and collected data of 30 patients having restrictive and 30 patients having obstructive lung disease. Thereafter, we compared the pulmonary function tests, FVC, FEV1% and PEFR in three groups. Result: Our observations show that as compared to normal values, in obstructive lung diseases, FVC remained same but there is decrease in FEV1% and PEFR. And in restrictive group of lung diseases, FVC is less than normal but FEV1% and PEFR are same as that of normal subjects. Conclusion: By our study we can conclude that pulmonary function tests like FVC, FEV1% and PEFR can be used to distinguish between obstructive and restrictive group of diseases.