In this paper, the lung cell A549 was used as a model. The protective effect of camphor (C. camphora) leaf essential oil on the A549 exposed to PM2.5 was investigated. Less than 1 mg/mL of essential oil had no effect on A549 cell proliferation, and low concentration had a certain promotion effect. 0.05～1.00 mg/mL essential oil had a significant antagonistic effect on cytotoxicity induced by PM2.5 (P＜0.05). The essential oilsignificantly reduced the content of MDA in the infected cells and increased the activity of SOD and CAT and the content of T-AOC (P＜0.05), indicating that the camphor leaf essential oil could antagonize the cytotoxicity of PM2.5 through antioxidant stress. The camphora leaf essential oilsignificantly reduced the content of TNF-α and IL-6 in the infected cells (P＜0.05), indicating that the camphor leaf essential oil could antagonize the cytotoxicity of PM2.5 by inhibiting the inflammatory reaction.