We report a case of metastatic brain tumor originated from pancreatic cancer, which might be clinically considered as rare and has been reported as a remarkably poor-prognostic disease. A 64-year-old male underwent pancreas tail resection for pancreatic cancer (R0 resection). Histological study revealed an invasive ductal carcinoma (T4N2M0, fStage IVb). Following a short term of GEM administration, S-1 (80 mg/m2,day 1-28/42 days) was administered as the second-line. After 7 courses of S-1 chemotherapy, a follow-up CT demonstrated lymph node recurrence in cervical and mediastinum region. S-1 administration was stopped and irradiation to these sites (60 Gy) resulted in PR. Two months after irradiation, dizziness and speech disturbance appeared, and MRI examination demonstrated a solitary brain metastasis, which was removed because of rapid worseness of neurological symptoms. Postoperatively, hemicereberal irradiation (30 Gy) was performed. After the brain surgery, no brain metastasis was appeared. The patient was alive with abdominal lymph node recurrence for 22 months after distal pancreatectomy. It was concluded from these findings that irradiation to systemic recurrence originated from pancreatic cancer might be effective as well as chemotherapy.