A 49-year-old man was admitted to our hospital with vomiting. Abdominal CT revealed an avascular tumor at the uncinate process of the pancreas measuring 36x30 mm. Preoperative serum CA 19-9 was 361 U/ml. During laparotomy,the tumor was deemed unresectable (T4NXM0, Stage IVa),and duodenojejunostomy was performed. External-beam radiotherapy (EBRT) (50.4 Gy/28Fr) with concurrent twice-weekly gemcitabine (GEM) (40 mg/m(2)/day) was delivered. In the outpatient setting, and 1,000 mg/m(2) of GEM was administered intravenously on days 1, 8, and 15. Cycles were repeated every 28 days. The patient received 13 cycles of GEM chemotherapy until the appearance of a grade 2 facial rash. A decrease in tumor size was observed, and the serum CA 19-9 level dropped to 16 U/ml. He remained well without any symptoms and pursued normal activity for 33 months. He died of peritoneal dissemination 43 months after diagnosis. Gemcitabine-based chemo-radiation seems to be a safe and effective regimen for unresectable pancreatic cancer.