A 71-year-old male was diagnosed with a non-small cell lung cancer (NSCLC) within the radiotherapy field that was used for the treatment of a small cell lung cancer (SCLC) 11 years ago. At the initial diagnosis in 1996 the patient had limited-stage SCLC located in the right upper lobe of the lung with mediastinal involvement. He received 4 cycles of chemotherapy and then mediastinal radiotherapy. With a complete response after chemoradiotherapy he was given prophylactic cranial radiotherapy After 11 years of disease-free period a new mass in left lower lobe of the lung was detected. Bronchoscopic biopsy showed second lung cancer with epidermoid histology. Although the incidence of a second lung cancer is higher in SCLC survivors, this is a unique case in the literature with second NSCLC developing in the previously irradiated side of limited-stage SCLC.