〔Abstract〕 Objective To explore the role of behavioral and psychological medicine in the standardized diagnosis and treatment of type 2 diabetes mellitus, in order to improve the effect of blood glucose control and the quality of life in patients. Methods A total of 60 patients with type 2 diabetes mellitus from Zhengzhou First People's Hospital Hangdong Community Health Service Center from June 2021 to June 2022 were selected as the research subjects and randomly divided into an observation group and a control group, with 30 cases in each group. The control group was given hypoglycemic drug treatment, while the observation group received behavioral and psychological medical intervention in addition to the treatment given to the control group. The treatment compliance, metabolic indicators [fasting plasma glucose (FPG), 2-hour postprandial glucose (2hPG), glycated hemoglobin (HbA1c), triacylglycerol (TG), total cholesterol (TC), low density lipoprotein chesterol(LDL-C)] before and after 1 year of treatment, quality of life, and the incidence of adverse events (hypoglycemia, emergency visits, hospitalization due to complications, severe hypoglycemia) were compared between the two groups. Results The treatment compliance rate in the observation group was 86.67%, which was higher than 56.67% in the control group, with a statistically significant difference (P < 0.05). The levels of FPG, 2hPG, HbA1c, TG, TC, and LDL-C after treatment in the observation group were lower than those in the control group, with statistically significant differences (P < 0.05). The quality of life scores (physical function, social function, mental health, vitality, emotional role, overall health) after treatment in the observation group were higher than those in the control group, with statistically significant differences (P < 0.05). The incidence of adverse reactions in the observation group was 16.67%, which was lower than 40.00% in the control group, with a statistically significant difference (P < 0.05). Conclusion Behavioral and psychological medicine can promote treatment compliance and improve metabolic indicators in patients with type 2 diabetes mellitus, which is beneficial for reducing the occurrence of adverse events, improving the quality of life, and enhancing prognosis.