Background: Critically ill children often require pain management or sedation due to their underlying conditions or the need for intensive care. However, the available drug options and their clinical reliability are frequently limited for these patients. This study explored the utility of sufentanil as an analgosedative in critically ill pediatric patients, drawing on clinical experience. Methods: This single-center retrospective observational cohort study included patients under 19 years of age admitted to the pediatric intensive care unit (PICU) in a tertiary care children's hospital between March 2021 and September 2022, in whom sufentanil was used as the first-choice continuous analgosedative drug. Results: In total, 225 patients were included. The most common reason for PICU admission was postoperative care (34.7%), followed by respiratory failure (20.0%), and cardiac problems (17.3%). The initial median starting and maximum doses of sufentanil were 0.5 μg/kg/hr (interquartile range [IQR], 0.3-1.0). The median durations of sufentanil use, mechanical ventilation support, and PICU stay were 1 days (IQR, 4-12), 6 days (IQR, 1-17) and 9 days (IQR, 5-27), respectively. In 199 (88.4%) patients, an appropriate analgesia/sedation level was achieved with sufentanil alone. However, 26 patients required additional drugs such as midazolam and ketamine infusion after administering the maximum dose of sufentanil, indicating the necessity for supplementary agents. No significant adverse effects or withdrawal symptoms were associated with sufentanil use. Conclusion: Sufentanil may be a promising option for analgesia/sedation in critically ill pediatric patients, as it demonstrated no significant side effects or withdrawal symptoms. However, larger-scale randomized controlled research is necessary to generalize these results.