Objective:To evaluate the therapeutic effect and mechanism of matrine and IFN-γin Bleomycin-induced pulmonary fibrosis of rats. Methods:Male SD rats(n = 60) were randomly divided into four groups:(A)normal group,(B)Bleomycin-induced pulmonary fibrosis model group,(C)Matrine group,(D)IFN-γ group.On days 7,14 and 28 after bleomycin treatment,5 rats in each group were killed, and the lung were harvested for histopathological studies,immunohistochemical determination of TGF-β1,CTGF,collagenⅠ and collagenⅢ. Results:The degree of alveolitis and fibrosis,the level of TGF-β1,CTGF,collagenⅠ and collagenⅢ decreased significantly in the groups C and groups D, as compared with groups B(P < 0.05). Conclusion:The treatment of Matrine or IFN-γ has some protective effects on pulmonary fibrosis in rats,partly through affecting TGF-β1 and CTGF expression.