Castleman's disease (CD) is a lymphoproliferative disorder and the occurrence of CD in the small bowel is rare. In this study, we present one case of CD causing mechanical intestinal obstruction due to involvement of terminal ileum. A 50-year-old man was admitted to the hospital with signs and symptoms of mechanical intestinal obstruction without history previous surgery. After examination and obtaining abdominal computed tomography, diagnosis of mechanical intestinal obstruction was reached and emergency surgery was performed with a median incision. On abdominal exploration a tumor like mass that also held distal small intestine mesentery, and ileocecal valve causing complet intestinal obstruction was observed. Ileocecal resection and ileocolonic anastomosis were performed. CD is a rare entity and should be kept in mind during the differential diagnosis of mechanical intestinal obstruction provided that wall thickening in terminal ileum mimicking mass, and accompanying enlargement mesenteric lymph nodes observed during preoperative investigations or intraoperative exploration.