This systematic review of randomized clinical trials (RCT) summarized the available evidence regarding the use of e-Health technologies for the treatment of depression, anxiety, and emotional distress in person with diabetes mellitus. The Cochrane CENTRAL, MEDLINE, EMBASE, Web of Science and LILACS databases searched were up to January 11th, 2023. The primary outcomes were improvement of depression, anxiety, diabetes-related emotional distress and quality of life. Reviewers, in pairs and independently, selected the studies and extracted their data. A total of 10 RCT involving 2,209 participants were analyzed. The methodological quality of the studies reviewed was high. Results showed improvements in depression with the use of Internet-Guided Self-Help (SMD = −0.74, 95%CI = −1.04 to −0.43) or Telephone-Delivered Cognitive Behavioral Therapy (CBT) (SMD = −0.42, 95%CI = −0.65 to −0.19); in anxiety with Internet-Guided Self-Help (SMD = −0.72, 95%CI = −1.02 to −0.42) or Diabetes-specific-CBT (SMD = −0.60, 95%CI = −1.18 to −0.02); and in emotional distress with Internet-Guided Self-Help (SMD = −0.72, 95%CI = −1.02 to −0.41) or Healthy Outcomes through Patient Empowerment (SMD = −0.26, 95%CI = −0.53 to 0.01) compared to usual care. Due to heterogeneity in interventions, populations, follow-up time and outcomes, future RCT should be conducted to confirm these findings.