Objective：To explore the effects of different titers of mycobacteriophage Chy3 on growth and function of human airway ep－ithelial cell 16HBE. Methods：Inverted microscope was used to observe cellular morphology after applying different titers of mycobac－teriophage Chy3. Cell viability and apoptosis rates were analyzed by CCK-8 assay and flow cytometry. Additionally，the secretion lev－els of IL-6/IL-8 in cell culture supernatant were detected by ELISA. RT-PCR and Western blot were performed to detect MUC5AC mRNA and protein expression. Results：There was no difference in cellular morphology，cell viability，apoptosis rate，secretion levels of IL-6/IL-8，MUC5AC mRNA and protein expression between cells treated with different titers of Chy3 and normal controls（P ＞0.05）. Conclusion：Neither high nor low titer of mycobacteriophage Chy3 exerts effects on growth and function of human airway epithelial cell 16HBE in vitro，therefore mycobacteriophage has better security.