Objective,2,To investigate the hypoglycemic effect of Tangfukang Formula on KK-Ay mice and its complex biological network relationship with intestinal flora.,Methods,2,Twenty-four 8-week-old SPF KK-Ay spontaneous diabetes model mice were randomly divided into 4 groups，namely model group，Tangfukang high-dose group，equivalent dose group and metformin group，with 6 mice in each group. Six C57BL/6J mice were used as normal control group. Normal control group and model group were given normal saline with intragastric administration，Tangfukang high-dose group，equivalent dose group and metformin group were given Tangfukang of 6.4 and 3.2 g/kg·d and metformin of 250 mg/kg·d with intragastric administration respectively. After 1 month of intervention，the sample was got and the blood glucose was detected，the pathological degree of skeletal muscle cells was observed under light microscope，and the structure of intestinal microflora of mice was analyzed by 16S rDNA sequencing.,Results,2,Tangfukang Formula could effectively reduce blood glucose，alleviate inflammatory infiltration and atrophy and necrosis of skeletal muscle，and significantly increase the diversity of intestinal flora，increase the relative abundance of bacteroidetes and decrease the relative abundance of firmicutes in mice.,Conclusion,2,Tangfukang Formula has a good hypoglycemic effect on KK-Ay mice，and its antidiabetic effect may be related to the regulation of intestinal microflora structure.