A 68-year-old woman with a chief complaint of obstructive jaundice was referred to our hospital. She was diagnosed with gallbladder cancer with invasion to the liver, extrahepatic bile duct, right hepatic artery and portal vein. After endoscopic retrograde biliary drainage, she received chemotherapy with gemcitabine and cisplatin. After 9 courses, the size of the tumor and the lymph nodes decreased, and we planned surgery. There were no unresectable factors, and the right hepatic artery and portal vein were detached from the tumor. We performed a subtotal stomach-preserving pancreaticoduodenectomy and gallbladder bed resection. We then performed adjuvant chemotherapy with S-1 for 1 year. The patient remains alive without recurrence, 5 years after the surgery. We report the case of advanced gallbladder cancer with downstaging after GC therapy.