Objective: Since 2012, the Korean Triage and Acuity Scale (KTAS) has been used to triage patients in an emergency care setting, and the KTAS provider course was started in 2014. However, due to the coronavirus disease 2019 (COVID-19) pandemic, this course could not be taught to learners face-to-face (FTFL). Therefore, a new KTAS course using synchronous online learning was launched in July 2020. This study investigated whether synchronous online learning (SOL) is as effective as traditional learning (FTFL) for KTAS education. Methods: This was a retrospective study of trainees who participated in the KTAS provider course in Seoul, Korea. The trainees were divided into FTFL and SOL groups. The post-test results of the two training methods were compared, and the association between the type of education and the training results was analyzed. Results: The mean post-test score of the FTFL and SOL groups were 78.16±12.4 points and 80.71±9.91 points, and the post-test pass rates were 79.2% and 82.1%, respectively. The mean difference (MD) between the two groups indicated the non-inferiority of SOL in the post-test scores (MD, 2.55; 95% confidence interval [CI], 1.35 to 3.75) and the pass rate (MD, 2.9%; 95% CI, -1.2 to 0.7). The results of the multivariate analysis revealed that the pass rate was associated with younger age and an emergency department career of over 18 months. However, there was no significant association between the education type and the results. Conclusion Through this study, SOL was shown to be as effective as FTFL in KTAS education. Furthermore, SOL may be the best alternative educational method during the COVID-19 pandemic because it has the advantage of resolving spatial restrictions.