AIM: To study the effects of trigliptin succinate on gut microbiota of type 2 diabetic mice. METHODS: 16S rRNA high-throughput sequencing method was used to sequence the intestinal flora of mice in the healthy group, the T2DM group, the trigliptin succinate group and the sitagliptin phosphate group. QIME was used to filter the data, classify and annotate the species. Alpha diversity index and Beta diversity index of the samples were analyzed.The richness and diversity of bacteria in the four groups were compared. RESULTS: The gut microbiota structure of mice in the healthy group, the T2DM group, the trigliptin succinate group and the setagliptin phosphate group were significantly different. The results showed that the ratio of Firmicutes to Bacteroidetes was decreased compared with that in the healthy group. Cyanobacteria, Verrucomicrobia and Tenericutes had significant differences (P< 0.05). Potential biomarkers for T2DM group were Bacilli, Lactobacillales, Lactococcus and Streptococcaceae. Candidate biomarkers of trigliptin succinate group may be Bacteroidia, Bacteroidetes, Bacteroidales, Prevotella, Paraprevotellaceae, Parabacteroides, Porphyromonadaceae; The candidate biomarkers of sitagliptin phosphate group may be Lactobacillus, Lactobacillaceae and Helicobacter. CONCLUSION: The intestinal flora of mice in the trigliptin succinate group was significantly different from that in the healthy group and the T2DM group. Using trigliptin succinate to improve the intestinal flora of mice might achieve the hypoglycemic effect by improving the intestinal flora.