Background Type 2 diabetes mellitus (T2DM) has become a public health burden facing the whole world, with the rapid development of Internet and digital technology, intelligent service model plays an important role in the management of patients with T2DM. Objective To explore the effectiveness of wearable devices combined with health coaching in patients with T2DM. Methods A total of 315 patients with T2DM who were hospitalized in the Second Affiliated Hospital of Nanchang University from June 2020 to June 2021 were selected as the study subjects, and divided into the control group, the intervention A group and the intervention B group based on the method of randomized numerical table, the control group implemented the routine management measures based on capillary blood glucose monitoring, the intervention A group adopted the wearable devices for routine management, the intervention B group was managed by wearable devices combined with health coaching. The differences in glycemic and lipid control status and self-management behaviors among the three groups before and 3, 6, 9 and 12 months after intervention were compared. Results A total of 15 lost visits were made during the implementation of the study, and 300 study subjects were finally included in the analysis, with 100 in each of the three groups. There was an interaction between intervention method and time in the three groups on 2-hour postprandial blood glucose (2 hPG) , glycated hemoglobin (HbA1c) , number of hypoglycemic episodes, low-density lipoprotein cholesterol (LDL-C) , self-management behaviors of diabetes mellitus (2-DSCS) , and self-management behaviors of diabetic patients (SDSCA) scores (P