Abstract：Objective To explore the value of traditional chinese medicine（TCM）of nourishing Yin and tonifying kidney combined with metformin for the function of inflammatory cells and vascular endothelium in diabetic patients with kidney-Yin deficiency syndrome. Methods A total of 94 diabetic patients with kidney Yin deficiency syndrome treated in our hospital from September 2018 to January 2020 were randomly selected as the observation group and control group according to the order of admission, 47 cases in each group. The patients in the control group were received metformin treatment and in the observation group were treated with TCM of nourishing Yin and tonifying kidney on the basis of the control group. The clinical efficacy of the two groups were observed. Before and after treatment, blood glucose and islet function indexes were compared between the two groups, including fasting blood glucose（FPG）, 2 h postprandial blood glucose（2 hPG）, glycosylated hemoglobin （HbA1c）, fasting insulin（FINS）, and 2 h postprandial insulin（PINS2 h）; the levels of inflammatory factors, including high-sensitivity C-reactive protein（hs-CRP）, interleukin-6（IL-6）, and tumor necrosis factor-α（TNF-α）, were compared between the two groups. Results The levels of blood glucose indexes, pancreatic islet function indexes, and inflammatory factors in the two groups after treatment were improved compared with those before treatment, and the improvement degree of the observation group was better than that of the control group, and the differences between the two groups were statistically significant（t＝5.717, 7.112, 1.387, 2.728, 2.937, 2.855, 8.163, 7.542, all P＜0.05）; the total effective rate of the observation group was higher than that of the control group, and the difference between the two groups was statistically significant（χ2＝12.136, P＜0.05）. Conclusion The TCM of nourishing Yin and tonifying kidney combined with metformin has obvious clinical curative effect on the treatment of diabetic patients with kidney-yin deficiency syndrome, which is beneficial to reduce blood glucose level, improve the function islet and vascular endothelium, and inhibit inflammatory cells, with high safety, can be popularized and applied in clinical practice.