A 51-year-old male patient presented with characteristic radiologic features of Crohn's disease in the terminal ileum plus a large tumorous lesion in the right lower abdomen. Because of rapid crescent symptoms of bowel obstruction, the patient underwent surgery revealing a high-risk gastrointestinal stromal tumor (GIST) of the terminal ileum within an area of Crohn's ileitis. Whereas the association of chronic inflammatory bowel disease (IBD) and gastrointestinal adenocarcinoma is well known, other primary intestinal tumors are rare in these patients, particularly at the time of onset of clinical symptoms. This is the 3rd patient reported in the literature with a sarcoma complicating IBD, and in fact, the first description of the coincidence of Crohn's disease and GIST. Though the present case is likely to be a mere coincidence of two pathologically distinct entities (without any potential causal relationship), it should remind one of the possibility of small bowel 'Crohn's carcinoma' in patients with a sudden change in symptomatology as well as in those in whom intestinal obstruction fails to resolve with adequate therapy.