To investigate the ameliorative effect of berberine on chronic atrophic gastritis(CAG) and its mechanism.Methods:SD rats were randomly divided into a control group，a model group，a low-dose berberine group，a medium-dose berberine group，a high-dose berberine group，and a DUSP19 group，with 9 rats in each group.Except the control group，CAG models were constructed.Berberine was given 25，50，and 100 mg/kg by gavage at low，medium，and high doses，respectively.The DUSP19 group was given 100 mg/kg of berberine by gavage and the tail vein was injected with 100 μ mol/L DUSP19，the protein tyrosine kinase 2/cytoplasmic transcription factor 3(JAK2/STAT3) pathway activator.The pathological changes were detected by hematoxylin-eosin(HE) staining.Western blot was used to detect the JAK2/STAT3 signaling pathway and apoptosis-related protein expression.Enzyme-linked immunosorbent assay(ELISA) was used to detect the expression level of serum-related factors.The apoptosis of gastric mucosa cells was detected by TdT-mediated dUTP Nick-End Labeling(TUNEL).Results:As compared with the model group，the levels of phosphorylated protein tyrosine kinase 2(p-JAK2)，phosphorylated protein tyrosine kinase 3(p-JAK3)，motilin(MTL)，and tumor necrosis factor-α(TNF-α)，interleukin 6(IL-6)，and interleukin 1β(IL-1β)，prostaglandin E2(PGE2)，endothelin(ET)，B-lymphoma toma-2 associated X protein(Bax)，cystatin 3(Cl caspase-3)，and cystatin 9(Cl caspase-9) and the cell apoptosis rate were significantly decreased(P<0.05)，while the levels of gastrin(GAS)，secretory immunoglobulin A(sIgA)，glutathione(GSH)，and B-lymphomatoma-2(Bcl-2) were significantly increased(P<0.05).DUSP19，the activator of JAK2/STAT3 pathway，significantly reversed the effect of berberine on the above indexes(P<0.05)，and HE results showed that berberine significantly improved the pathological changes in gastric tissues in rats with CAG.Conclusion:Berberine can alleviate CAG in rats by inhibiting apoptosis and inflammation through the JAK2/STAT3 signaling pathway.