Objective To analyze the effect of insulin glargine combined with acarbose in elderly diabetic patients and the effect on adverse reactions.Methods A total of 94 elderly patients with diabetes mellitus admitted to First People's Hospital of Tancheng from February 2022 to February 2023 were selected as the research objects,and they were divided into two groups according to different treatment methods,with 47 cases in each group.The control group was treated with insulin glargine,and the study group was treated with insulin glargine combined with acarbose.The blood glucose levels,islet function and adverse reactions were compared between the two groups.Results After treat-ment,the levels of fasting plasma glucose,2-hour postprandial plasma glucose and glycated hemoglobin A1c in the study group were lower than those in the control group,and the differences were statistically significant(all P<0.05).After treatment,the insulin resistance index of the study group was lower than that of the control group,and the insu-lin β cell secretion index of the study group was higher than that of the control group,and the differences were statisti-cally significant(both P<0.05).The total incidence of adverse reactions in the study group was lower than that in the control group,the difference was statistically significant(P<0.05).Conclusion The combination of insulin glargine and acarbose in elderly patients with diabetes mellitus can achieve good curative effect,which can not only control blood glucose level,improve islet function,but also reduce the incidence of adverse reactions.