Abstract: In order to evaluate the oxidative stress of human lung adenocarcinoma cells(A549 cells) induced by total particulate matter(TPM) in cigarette smoke,A549 cells were exposed to the TPM of mainstream smoke of 3R4F reference cigarette.The dose-response relationship between TPM dose and the viability of A549 cells was tested by the neutral red assay,and two indicators of oxidative stress,intracellular glutathione(GSH) and extracellular superoxide dismutase(EC-SOD),were determined.The results indicated that:1) A good dose-response relationship existed between TPM dose and the viability of A549 cells.2) When oxidative stress occurred,the rate of reduced and oxidized state glutathiones(GSH/GSSG) in cells significantly decreased comparing with negative control,it did not change with the increase of exposure duration.EC-SOD did not increase significantly in 4 hours,while it increased significantly after 24-hour exposure.The experimental results provide a reference for the research of cells'oxidative stress induced by cigarette smoke.