Introduction: Nitrogen dioxide (NO 2) can penetrate deeply into the sensitive parts of the lungs and cause or worsen chronic obstructive pulmonary disease (COPD), respiratory disease, emphysema, bronchitis and increased causes admission in hospital. Objective: The purpose of this study is the determination of COPD attributed to NO 2 in people's life of Bushehr megacity, Iran. Methods: This descriptive study was conducted in Bushehr during 2011. The chronic obstructive pulmonary disease data were calculated by utilizing indices of exposure risk to health effects NO 2. In this study, data were analyzed by SPSS. Results: According to the research findings, 60 and 15 μg/m 3 concentrations the yearly average NO 2 in Bushehr were the highest and the lowest. When the NO 2 concentrations were more than 10 μg/m 3 , 2.9% of admission happened to COPD. Low concentration of NO 2 was one of the reasons of a low percentage of the observed COPD. Conclusion: According to this study increasing the NO 2 concentration has a direct and a significant effect on chronic obstructive pulmonary diseases. Electrical heating, alternative fuels solar and cooking are important factors in decreasing the concentration of NO 2.