Objective:To investigate the effects of airborne fine particle on cell viability and inflammation in human bronchial epithelial cells.Methods:Atmospheric PM2.5 samples were collected by PM2.5 sampler.PM2.5 morphology was observed by scanning electron microscope (SEM).Human bronchial epithelial cells (BEAS-2B) were treated with PM2.5 at different concentrations (0,50,100,200,400,800 μg/mL) for 12,24 or 48 hours,and the cell activity were evaluated by cell counting kit-8 (CCK-8).The mRNA expression levels of (granulocyte-macrophage colony stimulating factor,GM-CSF) and TNF-α were detected by quantitative real-time PCR (qRT-PCR).Western blot was used to detect the protein expressions of GM-CSF and TNF-α.Results:According to SEM,the shape of PM2.5 varied,and the diameter was different and mostly equal to or less than 2.5 μm.CCK-8 assay showed that different concentrations of PM2.5 exposure for 12 hours,24 hours and 48 hours resulted in loss of cell viability of BEAS-2B cells (P＜0.05).Different concentrations of PM2.5 increased the mRNA and protein expression of GM-CSF and TNF-α,and the higher concentration of PM2.5 induced higher expression,which have statistical significant difference between the groups (P＜0.05).Conclusion:Atmospheric PM2.5 can cause inflammatory response in human bronchial epithelial cells.They can reduce cell viability,which may be related to the PM2.5 trigger and aggravation of bronchopulmonary inflammatory diseases.