The case of a 2-year-old boy suffering from a strangulated ileal herniation through Winslow's foramen into the lesser sac is reported. He presented an abdominal pain of sudden onset 16 hours previously. The clinical examination, abdominal x-ray, and sonography were not helpful in the assessment of the diagnosis of internal hernia, which was evoked by the computed tomography. At laparotomy, approximately 30 cm of the strangulated ileum was reduced through Winslow's foramen. Fifteen centimeters of the ileum was gangrenous and thus resected with an end-to-end anastomosis. Despite its congenital character, strangulated hernia of the ileum through Winslow's foramen is diagnosed more frequently in adulthood and exceptionally in childhood. Early diagnosis and treatment are crucial because of the high morbidity and mortality associated with strangulation.