A 57-year-old man had limited-disease small cell lung cancer in the left lower lobe of the lung. He was treated with chemotherapy with concurrent accelerated hyperfractionated thoracic radiation, followed by high-dose chemotherapy with autologous peripheral blood stem cell transplantation. He had obtained a complete response for 10 years until the tumor in the left lower lobe was detected by positron emission tomography. Bronchoscopic brushing cytology revealed small cell cancer, which was considered to be local relapse by staging work-up. He achieved a partial response with chemotherapy consisting of cisplatin and irinotecan. The progression-free survival rate at 5 years in limited-disease small cell lung cancer ranges from 10% to 25%. Although it was difficult to distinguish the relapse of lung cancer from second primary lung cancer, we considered this case as relapse because the tumor had the same cytology in the same lobe as the previous primary tumor. The residual cells refractory to concomitant chemoradiotherapy followed by high-dose chemotherapy with stem cell transplantation had survived and proliferated after 10 years.