Objective To analyze the effects of glargine insulin versus rapid-acting insulin on blood glucose levels and resuscitation efficiency in critically ill patients with diabetes mellitus.Methods A total of 80 cases of critically ill patients with diabetes mellitus admitted to Fujian Zhouning County Hospital between April 2021 and April 2023 were selected as the study objects,and were divided into the control group(40 cases,treated with rapid-acting insulin)and the observation group(40 cases,treated with glargine insulin)by the random number table method.Resuscitation suc-cess rate,blood glucose level,pancreatic islet function of the two groups were compared.Results The resuscitation success rate in the observation group was 95.00%higher than that in the control group 87.50%,but the difference was not statistically significant(χ2=1.409,P>0.05).After treatment,fasting blood glucose,glycated hemoglobin A1c,coeffi-cient of variation and homeostatic model assessment of insulin resistance were lower,fasting insulin was higher in the observation group compared with the control group,and the differences were statistically significant(all P<0.05).Conclusion The use of glargine insulin and rapid-acting insulin in critically ill patients with diabetes mellitus both have certain salvage effect,but the improvement effect of glargine insulin on patients'blood glucose and islet condi-tion is more significant,more conducive to optimize prognosis.