Objective: To study the effects of Weiyan I decoction (WID) on chronic atrophy gastritis (CAG) and the related molecular mechanism. Method: Ninety SD rats were divided into 4 groups: control group

model group and two treatment groups(1.08

0.54 g·kg-1). The CAG model was established in model group and treatment group

and the treatment of WID was continued for 12 weeks started from 20 weeks after model establishment. Afterwards

the pathological specimens of gastric mucosa were collected and investigated. The expression level of β-catenin and cyclin D1 mRNA were examined by RT-PCR. Result: Compared with the control group

the expression of β-catenin and cyclin D1 were increased in the model group

while treatment with WID could reduce the induction. The difference were significant (P<0.01). Conclusion: WID has good therapeutic effect on CAG. The mechanism of WID in treating CAG may be related with inhibition of the expression of β-catenin and cyclin D1.