We report a case of acute small bowel obstruction occurring secondary to endometriosis of the terminal ileum. Ileal endometriosis is a rare condition that can cause acute small bowel obstruction. As this case and others in the literature highlight, establishing a preoperative diagnosis is very difficult due to the vagueness of symptoms and similarity in presentation to other causes of obstruction, and is based on a high index of suspicion. However, this disorder should be considered in the differential diagnosis of women of child-bearing age who present with symptoms of obstruction. The definitive treatment includes resection of the involved segment with primary anastomosis, and adjuvant hormonal therapy may prevent recurrence.