Peptic ulcer disease is uncommon in children and rarely suspected as a cause of abdominal complaints in this age group; the diagnosis is therefore made almost exclusively when complications develop. Peptic ulcer disease is usually not considered in the differential diagnosis of pediatric patients. We present the case of a 30-month-old boy with duodenal perforation due to a peptic ulcer without a known etiology. The patient was admitted through the emergency department due to severe hematochezia and ongoing anemia; he presented with neither abdominal pain nor abdominal distension. There were no medical problems, and no drugs, such as corticosteroids or nonsteroidal anti-inflammatory drugs, had been prescribed or administered recently. We tried to control the active bleeding by medical treatment including arterial embolization, but the active bleeding was not controlled. Finally, an exploratory laparotomy was performed. A discrete anterior perforation with active bleeding of the duodenal wall was found. After the operation, there were no complications and the patient recovered fully.