Abstract: Objective To observe the expression of cell proliferation and apoptosis in congenital pulmonary cyst and investigate their effect in the development of aspergillus Methods Immunohistochemical method was used to detect the expression of KI-67、BCL-2 and BAX in normal lung tissue from 10 adult (control group 1，CG1)，relative normal lung tissue around the aspergillus from 20 aspergillus cases(control group 2，CG2)and abnormal lung tissue from 20 aspergillus cases. Results The expressions of KI-67,BAX and the ratio of BAX/BCL-2 in the bronchial epithelium of aspergillus were significantly higher than those in the two control groups（P<0.01）while the expression of BCL-2 was obviously lower（P<0.05）.In aspergillus cases, the ratio of BAX/BCL-2 in IPA was much higher than that in Aspergilloma and ABPA (p<0.05). Conclusion The imbalance of cell proliferation and apoptosis in the bronchial epithelium of aspergillus played an important role in the development of aspergillus.

Key words: Ki-67, Bcl-2, Bax, aspergillus, Immunohistochemistry