A very rare case of small bowel strangulation caused by herniation of a loop of ileum through a defect in the falciform ligament is reported. A 27-year-old woman in the 38 weeks and 5 days of pregnancy was admitted with a sudden onset of epigastralgia. Emergency laparotomy with cesarean section was performed. A strangulated loop of ileum was found to pass through a defect in the falciform ligament. The ligamentum teres was divided to release the obstruction and the irreversible strangulated loop was resected. The strangulation was considered to have occurred because a loop of small bowel compressed by gestational uterus passed through a congenital defect in the falciform ligament.