Primary linitis plastica of the colon, rectum and ileum is very uncommon, especially when it mimicks the colonic Crohn's disease. We observed this uncommon disease in a 26-year-old male. Barium enema showed characteristics of multiple consentric lesions in the entire colon, and some irregularity in mesenteric border of the terminal ileum. Colonofiberscopic finding showed multiple cobble stone appearance of the colon with a skipped area. The result of the biopsy illustrated that there was a poorly differentiated adenocarcinoma 5 cm from the anal verge. A longitudinal duodenal ulcer was discovered using the gastroscopic method. Upper gastrointestinal and small bowel series showed a suspicious gastric and duodenal Crohn's disease, and also showed ileum involvement. Operative finding showed a lead pipe appearance of the total colon, and the rectum was very fixed to the bladder and pelvic floor. The mesentery of the colon was thickened, and some portion of mesenteric creeping of the ileum was found to be mimicking Crohn's disease. The duodenal wall was also thickened. The biopsy result showed that there was a total involvement of the colon, rectum and ileum with signet-ring cell type adenocarcinoma with intact mucosa with the exception of a little portion of the rectum. This disease is very uncommon, and it is difficult to diagnose preoperatively, especially in Oriental countries.