Traffic-related air pollutants and particulates from diesel exhaust cause for increasing respiratory health problem. Recent epidemiologic studies have reported adverse effects of urban air pollution on various aspects of respiratory health. Bus or truck terminal workers have high probability of exposure to diesel exhaust particle than general office worker. This study was designed to evaluate the relationship between pulmonary function of people who working at the high-density area of diesel vehicles and pulmonary function of people who working at general office in Seoul. So, this study explored the effects on people with exposure to diesel traffic or exposure to diesel traffic, through the pulmonary function test (PFT). There were significant difference in Forced Vital Capacity (FVC) and Forced Expiratory Volume in 1 second () between high-exposure group and control. High-exposure to diesel particle were increased risk of reduction in pulmonary function in this study. These results provide the necessity additional research that manage people who working at the high-density area of diesel vehicles.