Lung cancer is one of the malignant tumors with high morbidity and mortality in the world. Lung cancer is divided into small cell lung cancer （SCLC） and non-small cell lung cancer （NSCLC），of which NSCLC accounts for about 85% of lung cancer. The traditional treatment of NSCLC mainly is surgery，chemotherapy，radiotherapy and targeted therapy. The emergence of immune checkpoint inhibitors takes the treatment of lung cancer into the era of immunotherapy. This article focused on the mechanism of immunotherapy，the new progress of immune checkpoints，the immunotherapy of advanced NSCLC and the latest research progress of immunotherapy in locally advanced NSCLC.