Abstract: Fine particulate matter (PM_2.5) may deposit in the alveoli through inhalation, and even penetrate the air-blood barrier into blood circulation. Therefore, it may induce the aggravation of airway inflammation and result in the development of acute exacerbation of chronic obstructive pulmonary disease (AECOPD). It has become an important public health problem due to the decline of quality of life and the increase of mortality of COPD patients. Herein, we summarize the progress of epidemiological studies about the impact of PM_2.5 on AECOPD, including characteristics of high-risk groups and seasonal variation. Meanwhile, the mechanisms of AECOPD induced by PM_2.5 are also described, and the strategies of prevention proposed.