Small cell lung cancer can receive immunotherapy. Some patients with small cell lung cancer whose conditions are more serious and have reached the advanced stage of the disease or whose effects of chemotherapy, radiotherapy and surgery are not satisfactory may consider receiving immunotherapy. At present, the commonly used immunotherapy drugs in clinic include atilizumab, carilizumab and so on, which can be used for the treatment of small cell lung cancer. However, before carrying out immunotherapy, it is necessary to carry out immune index PD-L1 index test, high expression can choose immune monotherapy, can also choose immune combined with chemotherapy program for effective control of the disease, and the effective rate is relatively high. the efficacy of immunotherapy for patients with low PD-L1 expression level is not obvious. Small cell lung cancer patients are advised to visit the respiratory department or oncology department of the hospital as soon as possible. Through improving genetic testing, imaging examination, histopathological examination, etc., to clarify the condition and receive standardized treatment.