Exposure to atmospheric fine particulate matters (PM_2.5) has already been recognized as a major public health problem. It can cause multiple adverse health effects, especially lung diseases. In this light, recent studies reporting ingredients potential mechanism of human lung toxicity induced by PM_2.5 exposure were reviewed in this article and presented in four categories including inflammatory response, oxidative stress, immune toxicity, and genetic mutations. This review aimed to provide a theoretical basis for further related study and the diagnosis of lung toxicity induced by PM_2.5.