Objective To study the possible mechanism of Tiaogan Lipi Fang（ 调肝理脾方） in the treatment of primary biliary cirrhosis. Methods Totally 120 C57 BL /6 rats were randomly divided into normal group

model group

positive group and treatment group

with 30 rats in each group. Except the normal group

the rats in the other groups received intraperitoneal injection of poly I-poly（ C） 5 mg / kg

twice a week

for 24 weeks to establish the animal model of primary biliary cirrhosis. Meanwhile

the positive group was given Ursodeoxycholic Acid Capules 0. 1 g /（ kg·d）

the treatment group was given Tiaogan Lipi Fang 27g /（ kg·d）

the normal group and the model group were given equal volume of normal saline

all by gavage once a day for 24 weeks. At the 8th

16 th

and 24 th week of the experiment

the positive rate of anti mitochondrial antibody M

2

subtype（ AMA-M

2

）

peripheral blood CD4

+

CD25

+

Foxp3

+

regulatory T cell（ Treg） count

and liver tissue pathological examination and expression of liver tissue and cell keratin 19（ CK19） were detected in all rats. Results There was no significant difference in the positive rate of AMA-M2 between the model group

positive group and treatment group at the 8th

16 th and 24 th week（ P

>

0. 05）. Compared with the normal group

the number of CD4

+

CD25

+

Foxp3

+

Treg cells in peripheral blood in the model group was significantly decreased at 8th

16 th and 24 th week（ P

<

0. 05）; At the 24 th week

the number of CD4

+

CD25

+

Foxp3

+

Treg cells in peripheral blood in the positive group and the treatment group was higher than that in the model group

but the treatment group was significantly higher than that in the positive group（ P

<

0. 05）.There was significant difference in the pathological staging of liver tissues between the treatment group and the model group at the 8th

16 th and 24 th week（ P

<

0. 05）. Compared with the normal group

the expression of CK19 in the model group was much higher than that in normal group at the 8th

16 th and 24 th week（ P

<

0. 05）; Compared with the model group

CK19 expression was decreased in the treatment group at the 24 th week（ P

<

0. 05）. Conclusion Tiaogan Lipi Fang can up-regulate the activity of CD4

+

CD25

+

Foxp3

+

Treg in peripheral blood and reduce the expression of CK19 protein in liver tissue of rats model with primary liver cirrhosis

so as to improve the bile duct injury and hepatic fibrosis.