This study aims to investigate Tujia medicine Berberidis Radix on intestinal flora of mice with ulcerative colitis induced by dextran sodium sulfate and provide the scientific basis for its development and utilization.c57BL/6J mice were randomly divided into normal group,model group,mesalazine group,and low-,medium-,and high-dose Berberidis Radix groups.Except for the normal group, 2.5% dextran sodium sulfate drinking water was given to each group for seven days.At the same time,the administration group was gavaged with the mesalazine group and Berberidis Radix group for ten days.Body weight changes and disease activity index were measured.Hematoxylin-eosin staining was used to observe the pathological changes in colon tissue.The composition and diversity of the intestinal flora were detected by 16S rRNA gene sequencing.The results demonstrated that Berberidis Radix could significantly decrease disease activity index score(P＜0.05).Berberidis Radix improved species richness and diversity in the intestinal flora of mice with ulcerative colitis and adjusted the abundance of the dysregulated bacteria closer to that of the normal group.This study reveals that regulating the diversity of intestinal flora and the structure of flora may be one of the essential ways for Berberidis Radix to intervene in ulcerative colitis and provides a theoretical basis for the clinical use of Berberidis Radix through the perspective of intestinal flora.