Objective:To investigate the clinical effect of the hospital preparation Manwei Granule on the treatment of patients with chronic atrophic gastritis（CAG） based on the theory of"decomposing the subject and the object". Methods:A total of 80 patients with CAG were randomly divided into treatment group（treated with Manwei Granule） and control group（treated with Weifuchun Tablet）

with 40 patients in each group

and clinical outcome was observed after treatment. Results:After treatment

the treatment group had improvements in the mean scores of traditional Chinese medicine symptoms（stomach bilges or epigastric pain

belching

acid reflux

poor appetite

and weakness）

mucosal image on gastroscopy

and the degree of mucosal atrophy

with a significantly better clinical outcome than the control group（P < 0.05）. Compared with the control group

the treatment group had significantly greater increases in mean serum pepsinogen I（PG I） level and pepsinogen I/II ratio（PGR）（P < 0.01）. Conclusion:The method of"decomposing the subject and the object"has a marked clinical effect in the treatment of CAG

possibly by affecting serum PGI and PGR.