Small bowel obstructions are most commonly caused by adhesions, hernias, neoplasms or inflammatory stricture. Inflammatory pseudotumors are an uncommon cause of small bowel obstruction, even in a patient with acquired immunodeficiency syndrome (AIDS). We have experienced a case of small bowel obstruction caused by an inflammatory pseudotumor in a 38-year old male with AIDS. Abdominal computed tomography showed small bowel obstruction due to jejunal annular wall thickening. Surgical laparotomy showed a non-specific granulomatous inflammatory mass that could not fulfill any diagnostic criteria for a specific disease. This report describes our findings of small bowel obstruction due to an inflammatory pseudotumor and discusses the differential diagnosis of inflammatory pseudotumor in AIDS patients. (Korean J Gastrointest Endosc 2011;42:250-254)