The study of respiratory functions is evaluated by means of Pulmonary Function Tests. PEFR is defined as "the largest expiratory flow rate achieved with maximum forced effort from a position of maximal inspiration expressed in litre/ minute." In our present study we intend to study the PEFR in young healthy adult nonsmoker males of Aligarh between the age group of 18-40 years, simultaneously taking into account other anthropometric parameters. We observed from our study that PEFR is significantly correlated with all the anthropometric parameters in total subjects except the body weight. Amongst the respiratory parameters PEFR is significantly correlated only with maximum expiratory pressure. PEFR has significant positive correlation with handgrip strength. It is clearly evident from the above findings that the predicted values of PEFR are very close to the observed values. The derived equation can be used a prediction equation for estimating the PEFR in healthy adult males of Aligarh city. Therefore this study can be used to predict pulmonary function status of general population of the city and for clinical purposes especially for the management of obstructive lung diseases.