Crohn's disease and ulcerative colitis are well known risk factors of intestinal cancer in relation to the extent and duration of disease. Rarely, small bowel cancer can develop after a longstanding inflammation of Crohn's disease with a relatively higher incidence than the general population. Signet ring cell carcinoma is a rare condition among intestinal cancers, and the diagnosis or detection is more difficult if the cancer originates from the small bowel. We report a case of a 30-year old female in whom signet ring cell carcinoma of ileum was diagnosed after a 15-year history of Crohn's disease.