Objective:To investigate the clinical efficacy of insulin degludec/insulin aspart on type 2 diabetes mellitus in patients with poor efficacy of oral hypoglycemic drugs.Methods:A total of 100 patients with type 2 diabetes mellitus in Tianfu Hospital of Chongqing Energy Investment Health Industry Company Limited from August 2020 to August 2021 were included in this study. They were randomly assigned to receive either insulin degludec/insulin aspart combined with Metformin (observation group, n = 50) or nsulin aspart 30 injection and Metformin (control group, n = 50). All patients were treated for 3 months. Changes in fasting plasma glucose level, 2-hour postprandial glucose level , and HbAlc after treatment relative to those before treatment as well as clinical efficacy were determined in each group. Results:Forty-eight patients in the observation group and forty-six patients in the control group completed the course of treatment. Fasting blood glucose level and 2-hour postprandial glucose level in the observation group were (6.24 ± 1.12) mmol/L and (8.34 ± 2.34) mmol/L, respectively and they were significantly lower than (6.91 ± 1.86) mmol/L and (10.72 ± 2.48) mmol/L, respectively in the control group ( t = 3.28, 4.76, both P < 0.05). The level of HbAlc was not significant between the two groups ( P > 0.05). The hypoglycemia rate in the observation group was significantly lower than that in the control group [2% (1/48) vs. 13% (6/46), χ2 = 4.09, P < 0.05]. The daily dose of insulin in the observation group was less than that in the control group [(13.5 ± 2.8) IU vs. (15.6 ± 3.1) IU, t = 3.28, P < 0.05)]. Conclusion:Compared with insulin insulin aspart 30, the insulin degludec/insulin aspart has a stronger hypoglycemic effect on fasting plasma glucose level and 2-hour postprandial glucose level in the treatment of type 2 diabetes mellitus in patients with poor efficacy of oral hypoglycemic drugs, leading to a less daily dose of insulin.