Although it has been reported that the risk of second malignancies increases in long-term survivors of small cell lung cancer (SCLC) and late recurrence of SCLC is sometimes experienced, it seems uncommon. We recently experienced a case of redevelopment of SCLC after a long disease-free period. The case was considered to be second primary SCLC more than 10 years after the initial treatment. The necessity for lifelong follow-up in long-term survivors of SCLC is emphasized.