Behavior and lifestyle interventions (BLIs) can reduce blood glucose and blood pressure, regulate blood lipids, control obesity, reduce cardiovas cular events and are a first-line treatment for chronic diseases such as diabetes mellitus. BLIs include helping patients maintain a healthy diet, adhere to physical exercise, maintain a normal weight, ensure good sleep, avoid smoking and alcohol abuse, make good psychological adjustments, establish good social support, as well as scientific self-monitoring of blood glucose and adherence to drug therapy. Except for the severe hyperglycemia and acute complications requiring medication, patients with newly diagnosed diabetes mellitus should first undergo BLIs. BLIs should follow the principles of effectiveness-centered, mutual trust establishment, problem-solving orientation, integration, and individulization. Common strategies for BLIs include applying behavior change theories, utilizing behavior change technologies, effectively emlpoying communication strategies, improving patient behavior skills, and implementing patient-centered self-management education and support (DSMES). The steps of BLIs include evaluating behavior, lifestyle and their influencing factors, setting behavioral goals, developing intervention plans, and conducting interventions and effectiveness evaluation. The evaluation measures for the effectiveness of BLIs include process indicators, clinical outcomes, socio-psychological and behavioral outcomes, patient reports, and health outcomes. Evaluation can be performed using a combination of qualitative and quantitative methods. Common evaluation tools include the SDSCA, PAM, and DMSES.