Objective: To investigate the clinical efficacy of Bolus of Six Drugs Including Rehmannia (Liuwei Dihuang pill) as an adjunct to metformin in the treatment of senile Type-2 diabetes mellitus and its influence on insulin resistance, inflammatory factors and blood glucose-related indexes. Methods: This is a Retrospective study. Eighty senile Type-2 diabetes mellitus admitted to Baoding Hospital of Traditional Chinese Medicine from January 2019 to December 2021 were enrolled and divided into two groups using the random number method. Patients in the control group were given oral metformin, while those in the observation group were treated with Bolus of six Drugs Including Rehmannia as an adjunct to metformin. The clinical efficacy, blood glucose-related indicators, insulin-related indicators, inflammatory factors-related indicators and adverse drug reactions were compared between the two groups. Results: The overall response in the observation group was higher than that in the control group(P<0.05). After treatment, the levels of FPG, 2hPG and HbA1 being more significantly lower in the observation group than that in the control group(P<0.05). Moreover, the levels of FINS, HOMA-IR and HOMA-IS were all significantly improved in the observation group than that the control group (P<0.05). HOMA-β levels in the observation group were significantly higher than those in the control group (P<0.05). The levels of TNF-α, IL-6 and IL-8 in the observation group were significantly lower than those in the control group (P<0.05). Conclusion: Bolus of six Drugs Including Rehmannia as an adjunct to metformin is a regimen with satisfactory safety profile for the treatment of senile Type-2 diabetes mellitus. doi: https://doi.org/10.12669/pjms.39.5.7262 How to cite this: Li N, Yao Y, An E. Clinical Efficacy of Bolus of Six Drugs Including Rehmannia as an Adjunct to Metformin in the Treatment of Senile Type-2 Diabetes Mellitus and its Influence on Insulin Resistance, Inflammatory Factors and Blood Glucose-related Indicators. Pak J Med Sci. 2023;39(5):---------. doi: https://doi.org/10.12669/pjms.39.5.7262 This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.