A 62-year-old man presented with pruritus caused by obstructive jaundice. He was diagnosed with carcinoma of the ampulla of Vater and underwent pylorus-preserving pancreaticoduodenectomy. Histologic examination revealed signet-ring cell carcinoma without nodal metastasis. The patient underwent a partial resection of the small bowel for small bowel obstruction 38 months after the initial resection. Histologic examination disclosed signet-ring cell carcinoma at the surface of the resected small bowel, and the diagnosis of peritoneal recurrence was confirmed. He received oral S-1(100 mg/day) every other day for 14 months until bowel obstruction caused by peritoneal carcinomatosis became apparent. The patient died of the disease 58 months after the initial resection.