PURPOSE: This study aimed to identify the characteristics of interventions employed to promote behavior change in people with type 2 diabetes mellitus (T2DM) and their impact on disease self-management and glycated hemoglobin (A1c). METHODS: The Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines were used to guide the protocol development for this systematic review. Randomized controlled clinical trials which compared behavior change interventions to controls in adults with T2DM and investigated disease self-management and glycated hemoglobin (A1c) measured by validated methods were eligible for this study. The risk of bias and quality of evidence was assessed respectively by Cochrane's tool and grading of recommendations, assessment, development, and evaluation (GRADE). RESULTS: A total of 27 studies were included involving 4464 participants. Behavior change was mainly promoted by education sessions on diabetes care delivered face-to-face, monthly, or every other month, lasting more than 60 min, involving blood glucose monitoring, healthy eating, exercise, and medication. Four studies showed significant improvement in both disease self-management and A1c. The risk of bias was classified as high in most studies. A meta-analysis could not be performed for A1c and self-management due to the high differences in intervention parameters (delivery mode, number, duration, and frequency) and self-management assessments. CONCLUSION: Low evidence of improvement in disease self-management and A1c considering only validated assessment methods were found for behavior change interventions, mainly promoted by education sessions on diabetes care. The quality of studies and probably the differences in intervention protocols contributed to this finding.