Abstract: ObjectiveTo explore the expression changes of miR-16 and bcl-2 in the A549 lung cancer cell lines treated with Cisplatin. MethodsThe growth inhibition rate of lung cancer cells was analyzed by MTT assay, the number of dead cells was determined by counting of trypan blue exclusion staining cells and the morphology of A549 cells was observed by the inverted microscope to deter mine the appropriate Cisplatin concentration. Then the miRNA was extracted from the A549 cells, the changes of miR-16 expression in the control group and the dosing group were analyzed by Real-time PCR and miRNA's downstream regulating genes were evaluated by microRNA--org analysis software. The expression of bcl-2 protein in the two groups was detected by Western blot. ResultsAfter Cisplatin treatment, the number of A549 dead cells was significantly increased. The expression of miR-16 in Cisplatin group was significantly higher than that in the control group. However, the expression of bcl-2 protein in Cisplatin group was lower than that in control group. ConclusionCisplatin induced lung cancer A549 cell apoptosis; miR-16 down-regulated the expression of bcl-2 protein as a tumor suppressor genes, involved in the mechanism of A549 cell death induced by Cisplatin.