The case of a 50-year-old woman with pathologically proven tuberculous colitis is reported. Clinical course, single-contrast barium enema, and colonoscopy suggested Crohn's disease. Computed tomography allowed the correct diagnosis of tuberculous colitis as it showed asymmetric thickening of the colonic wall and enlarged necrotic lymph nodes. This case suggests that the diagnosis of tuberculous colitis may be difficult and raises the differential diagnosis with Crohn's disease. Our observation suggests that computed tomography can be helpful for the diagnosis and may avoid unnecessary exploratory laparotomy.