Objective:To observe the effect of total alkaloids of Desmodium pulchellum on collagen deposition and express of TGF β 1 in mouse liver which were made into immunity hepatic fibrosis model, study the action of restraining hepatic fibrosis and probable effective mechanism.Methods:bo mouse were diveded into model group, positive contrast group, normal contrast group and alkaloid groups of high, medium and low concentration. Injecting pig serum into mouse abdominal cavity to induce hepatic fibrosis model. At the same time, alkaloid groups of high, medium and low concentration were given total alkaloid of Desmodium pulchellum at does of 30mg/kg, 20mg/kg and 10mg/kg respectively for eight weeks. After liver tissue was dyed into HE, the necrotic degree of liver tissue and deposition change of collagen fibre. were observed. The express of collagen protein(Ⅰ,Ⅲ,Ⅳ)and the effect on TGF β 1 were observed by immunohisto chemistry.Results:Comparing with the normal contract group, the model group had shown typical hepatic fibrosis. The interval of collagen fibre had been formed extensively. Collagen in lobules of liver and hepatic sinusoid haven grown up and deposited obviously. The number of collagen(Ⅰ,Ⅲ,Ⅳ)were 1 28±2 59,1 00±1 22 and 1 03±1 46 while those of model group were 13 82±6 55,14 69±7 16 and 12 44±6 89,so the number of P in statistics was lower than 0 001. The express of TGF β 1 increased obviously. Alkaloid groups could alleviate collagen hyperplasia and deposition obviously in liver( P <0 05) and restrain the express of collagen protein(Ⅰ,Ⅲ,Ⅳ) ( P <0 05) and synthesis of TGF β 1.Conclusion: Total alkaloid of Desmodium pulchellum can restrain collagen protein(Ⅰ,Ⅲ,Ⅳ)and synthesis of TGF β 1 for hepatic fibrosis in mouse liver amd therefore.