After recurrence of small cell lung cancer, comprehensive treatment is the mainstay, including chemotherapy, immunotherapy and targeted therapy. 1. Chemotherapy: chemotherapy is the basic treatment for patients with recurrent small cell lung cancer, and commonly used chemotherapeutic drugs include topotecan, irinotecan, paclitaxel, docetaxel and so on. Patients with previous history of chemotherapy can also adopt the original chemotherapy program. 2. Immunotherapy: Patients with recurrent small cell lung cancer can be tested for PD-L1 expression level. If the PD-L1 expression level is more than 50%, immunotherapy alone can be used. If PD-L1 expression level is greater than 50%, then immunotherapy alone can be used. If it is greater than 5% and less than 50%, then chemotherapy combined with immunotherapy can be used. Clinical guidelines recommend atilizumab and navulizumab. 3. Targeted therapy: the third-line targeted drug recommended by clinical guidelines is anilotinib, which has been shown to prolong the survival time of patients with recurrent small cell lung cancer to a certain extent in relevant clinical studies. In addition to the above treatments, patients with recurrent small cell lung cancer can also take some palliative treatments to alleviate their pain, and it is recommended that patients go to the hospital as soon as possible and ask professional doctors to formulate scientific and reasonable treatment plans.