Background and Objectives: The coronavirus disease 2019 (COVID-19) pandemic has profoundly impacted healthcare systems worldwide. To assess the effects of the pandemic on pediatric emergency department (ED) visits in Taiwan, we conducted a study to evaluate changes in pediatric ED visits during the COVID-19 pandemic. Materials and Methods: This retrospective study included pediatric patients (age ≤ 18) who visited the ED between 21 January 2019 and 30 April 2019, at three hospitals of the Cathay Health System, and compared them with a corresponding period in 2020. Basic information, including mode of arrival, triage level, disposition, chief complaints, and incidence rates, were analyzed before and during the pandemic. Results: A total of 10,116 patients, with 6009 in the pre-pandemic group and 4107 in the pandemic group, were included in this study. The mean number of daily pediatric ED visits decreased from 60.09 before the pandemic to 40.66 during the pandemic, while ambulance use increased significantly by 2.56%. The percentage of patients with high acuity triage levels (levels 1 and 2) was significantly lower during the pandemic period (0.63% and 10.18%, respectively) than the pre-pandemic period (0.7% and 10.9%, respectively). Additionally, a significantly higher proportion of patients were discharged during the pandemic period (89.36%) than during the pre-pandemic period (88.33%). The proportion of COVID-19-related complaints, such as fever and respiratory tract infections, as well as other complaints including gastrointestinal issues, trauma, and psychological problems, significantly increased during the pandemic. Conclusions: In preparation for future pandemics, we recommend increasing emergency medical service capacity, establishing a non-contagious route for obtaining chronic medication prescriptions, optimizing staff allocation in pediatric emergency departments, and increasing the number of hospital social workers for enhanced support.