Air fine particulate matter (PM_2.5) pollution has become an important factor affecting human health, and its health effects and inflammatory mechanisms have been widely concerned by people. This article briefly describes the pollution status at home and abroad. The harm to human health was systematically expounded in terms of the chemical components of PM_2.5. In addition, the toxic mechanism of PM_2.5 causing body inflammation was summarized and discussed from two aspects of signal pathway and autophagy, so as to provide the corresponding scientific reference basis for the followup research and control of the harm of atmospheric particulate matter to body health.