In children, duodenal hematomas following blunt abdominal trauma are routinely treated conservatively. A case of a two-and-a-half-year-old female in whom conservative management was unsuccessful is presented. At surgery she was found to have an atretic duodenum secondary to the duodenal hematoma. Although uncommon, fibrotic stenosis must be considered in a patient who fails to show resolution of duodenal obstruction following conservative treatment for a duodenal hematoma.