Abstract: In this report, the¹³¹ I-HIPDM metabolism in the lung was studied on the 6 normal nonsmoking subjects, 8 normal smokers, 10 nonsmoking COPD patients, 7 patients with COPD of smokers and 5 bronchial asthma of nonsmokers. 31 of them were submitted to spirome-try and arterial blood gas analysis. The results showed that the clearance curve of ¹³¹I-HIPDM displayed difference in the different group. The analysis of ¹³¹I-HIPDM of the lung clearance may form a new index of lung dysfunction. The lung clearance of ¹³¹I-HIPDM has good corelation with FVC, FEVl, FRC, RV, TLC, PEFR, VC, MVV and Pa02. The speed of ¹³¹I-HIPDM of the lung clearance reflects the condition of lung function and may be a better lung functional marker in different stages of disease and early lung function injury.