A model of infectious bronchit was developed in SPF chickens by repeated intranasal infectious routes,and then the influence of compound Chinese traditional medicine on cellular immunity and humoral immunity during preventing and curing infectious bronchitis was studied by MTT,flow cytometry and serum neutralization test in tracheal organ culture.The results showed that compared with the infected group,the compound Chinese traditional medicine group could significantly increase the weight gain of chickens(P<0.05),promote the growth of immunity apparatus,enhance the T lymphocytes proliferate response of chickens and increase serum neutralization antibody titers of chickens significantly(P<0.05),and the ratio of CD4+/CD8+T lymphocytes was improved significantly(P<0.01).The aforementioned results indicated that the compound Chinese traditional medicine could reinforce immune function via preventing both cellular and humoral immunity from depression in the chickens with IBV.