Acute pancreatitis is a rare complication during chemotherapy for pediatric patients with solid tumors. We report a 9-year-old boy with osteosarcoma who experienced 2 episodes of pancreatitis 1 day and 48 days after infusion of ifosfamide (IFOS), respectively. From a MEDLINE search, this is the 3rd reported case and 2nd reported pediatric case of IFOS-induced pancreatitis, and only this case experienced late-onset pancreatitis.