We report a case of a highly advanced urothelial carcinoma accompanied by duodenal stenosis with pancreaticoduodenectomy. A6 6-year-old man presented with upper abdominal pain and vomiting. Acute pancreatitis and hydronephrosis were diagnosed with urgent hospitalization, but jaundice appeared, and stenosis of the duodenum was also found. Thus, we suspected groove pancreatitis or pancreatic cancer, and performed pancreaticoduodenectomy. However, poorly differentiated adenocarcinoma was observed in the retroperitoneal dissection surface in the intraoperative rapid tissue and right hemicolectomy, right nephrectomy, and right ureteral resection were added to the diagnosis. The final diagnosis was urothelial carcinoma. GEM plus CBDCAtherapy was administered as adjuvant chemotherapy. However, obstructive jaundice, acute cholangitis, and acute pancreatitis developed due to occlusion of the intestine due to local recurrence 4 months after surgery. We attempted to reduce yellowing by PTCD; perforation of the small intestine also occurred and a drainage tube was placed in the abdominal cavity. Although a lull condition was obtained, intestinal obstruction due to cancer peritonitis worsened and the patient died 8 months after the operation. In this case, there was no hematuria before surgery and cytology results of urine were negative, so a diagnosis of urinary tract cancer was difficult. There was no report of duodenal stenosis due to urothelial carcinoma.