Background: The therapeutic response in SCLC ptients for 1st line chemotherapy using platinum is closely related with prognosis. So we hypothesize that therapeutic response for chemotherapy using platinum is correlated with SUV-max value in PET-CT which is known to be correlated with prognosis in SCLC patients. Methods: We retrospectively reviewed the medical records of the patients who are diagnosed as SCLC pathologically or cyto-logically in two university hospital from January 2007 to December 2011. We grouped all patients into good-response group and poor-response group. Good-response group is the patients who are platinum-sensitive patients (recurred after 4 month later after finishing chemotherapy using platinum). Poor-response group is the patients who are platinum-resistant patients (recurred before 3 months after finishing chemotherapy using platinum) and progressive disease patients for WHO criteria. We excluded patients who had no PET-CT data or no chemotherapy data. Results: Of the total of 64 screened patients, 24 patients met the enrollment criteria. Good-response group (platinum-sensitive patients) are 10 patients, and poor-response group are 14 patients (platinum-resistant patients are 10 patients, and progressive disease patients are 4 patients). There is no significant association between therapeutic response and SUV-max value in PET-CT. Conclusions: There is no significant association between therapeutic response and SUV-max value in PET-CT. So we conclude that we cannot predict the therapeutic response with SUV-max value in PET-CT.