INTRODUCTION: The objective of this study was to systematically review the literature and perform a meta-analysis comparing the clinical outcomes of telehealth and usual care in the management of diabetes. METHODS: Multiple strategies, including database searches (MEDLINE, PsycINFO, PubMed, EMBASE, and CINAHL), searches of related journals and reference tracking, were employed to widely search publications from January 2005 to December 2017. The change in hemoglobin A1c (HbA1c) levels was assessed as the primary outcome, and changes in blood pressure, blood lipids, body mass index (BMI), and quality of life were examined as secondary outcomes. RESULTS: Nineteen randomized controlled trials (n = 6294 participants) were selected. Telehealth was more effective than usual care in controlling the glycemic index in diabetes patients (weighted mean difference = -0.22%; 95% confidence intervals, -0.28 to -0.15; P < .001). This intervention showed promise in reducing systolic blood pressure levels (P < .001) and diastolic blood pressure levels (P < .001), while no benefits were observed in the control of BMI (P = .79). For total cholesterol and quality of life, telehealth was similar or superior to usual care. CONCLUSION: Telehealth holds promise for improving the clinical effectiveness of diabetes management. Targeting patients with higher HbA1c (≥ 9%) levels and delivering more frequent intervention (at least 6 times 1 year) may achieve greater improvement.