Background Telehealth services were used by healthcare centers during the COVID-19 pandemic in order to identify and manage patients at the forefront of the healthcare system. As one of these technologies, tele-triage refers to the assessment of a patient's health status through telephone or another means of communication and recommending treatment or providing appropriate referrals in emergency rooms and primary care offices. This study aimed to perform a systematic review of the evidence on the effectiveness of tele-triage, as one of these technologies, during the COVID-19 pandemic. Methods Medline (via PubMed), Scopus, and Web of Science databases were searched for relevant English articles published since the pandemic's onset until December 30, 2021. Studies investigating the tele-triage's effect on patient safety, clinical outcomes, and patient satisfaction were included. Data on study characteristics, intervention characteristics, and their effects on study outcomes were extracted separately by two authors. A narrative synthesis of the included studies was ultimately performed. Results Out of the 6312 retrieved studies, 14 met the inclusion criteria. The tele-triage intervention was offered by an algorithm-based system in eight studies (57.14%) and by healthcare providers in six other studies (42.86%) to determine the patient's level of care. According to the results, tele-triage interventions during COVID-19 can reduce unnecessary emergency room visits (by 1.2–22.2%), improve clinical outcomes after intervention (such as would closure in diabetic feet), reduce mortality and injuries, and ensure patient satisfaction with tele-triage (53–98%). Conclusions This study found that tele-triage interventions reduced unnecessary visits, improved clinical outcomes, reduced mortality, and injuries, increased patient satisfaction, reduced healthcare provider workload, improved access to primary care consultation, and increased patient safety and satisfaction. Therefore, tele-triage systems are not only suitable for providing acute and emergency care remotely but they are also recommended as an alternative tool to monitor and diagnose COVID-19.