Background: Particulate matter (PM) is widespread air contaminants including a complex mixture of solid and liquid particles suspended in the air. Though epidemiologic studies have demonstrated a relation between exposure to PM and several dermatologic disorders, molecular mechanism of PM induced skin damage is still unknown. Objectives: This study aimed to investigate the influence of PM on the epidermal inflammation and skin aging. Methods: Human keratinocytes (HaCaTs) were treated with PM. The cell viability was assessed by MTT assay. The reactive oxygen species (ROS) generation was measured by DCFH-DA assay. The gene expression, protein expression and levels of inflammatory cytokines were assessed by RT-qPCR, Western blot and ELISA. Results: Translocation of aryl hydrocarbon receptor (AhR) protein into nucleus was detected at 2 hours after PM treatment. Additionally, PM increased intracellular ROS levels, pro-inflammatory cytokines and mRNA expression of CYP1A1 and CYP1B1 in dose-dependent manner. The phosphorylation of JNK, p38, c-Jun, c-Fos, and p65 were up-regulated by PM. Conclusion: PM aggravates oxidative stress and inflammatory response via upregulation of AhR signal pathway. Therefore, PM could be the one of the causes of skin aging and inflammation.