To explore the effects of Sijunzi Decoction，Maxingshigan Decoction，the combination of Maxingshigan and Sijunzi Decoction on the diversity of intestinal flora in normal mice.Methods:A total of 20 Balb/c mice were randomly divided into 4 groups：the normal group，the Sijunzi Decoction group，the Maxingshigan Decoction group，the combined Maxingshigan and Sijunzi Decoction group，with 5 mice in each group.Sterile double distilled water was administrated to the normal group by gavage，while the other 3 groups were given the corresponding decoction by gavage.The feces of mice in each group were collected aseptically on the 4th and 7th day of gavage.The 16S rRNA high-throughput sequencing method was used to detect the changes of microbial community structure and diversity in the feces of mice in each group.Results:The intervention of each drug resulted in changes in the numbers of OTU(operational taxonomic unit）in the intestinal flora of normal mice，and the increase in the abundance of the Maxingshigan Decoction group was especially significant(P<0.05).In the two time periods，the Shannon indexes of all traditional Chinese medicine groups were different from that of the normal group，and the increase of the flora diversity of the Mmaxingshigan Decoction group was more significant.Compared individually with each drug group，the number of OTUs shared between the normal group and the Sijunzi Decoction group was the highest，and the similarity of the two intestinal floras was the highest.The use of drugs changed the structure and proportion of dominant bacteria in the intestinal tract of mice.The total microflora of mice in the drug groups and the normal group were significantly isolated from each other.The use of Sijunzi Decoction and the combination of Maxingshigan and Sijunzi Decoction can significantly increase the abundance of bacteria related to SCFA production.Conclusion:Compared with the normal group，the structure and diversity of intestinal flora of mice in every Chinese medicine group changed significantly.