Progress in the field of cancer immunotherapy with programmed cell death protein 1/programmed death-ligand 1 (PD-1/PD-L1) checkpoint inhibitors has profoundly influenced the treatment of lung cancer. The survival benefits of these agents compared with those of standard treatments have been demonstrated in patients in first and second lines as well as in maintenance settings after chemoradiotherapy. However, while the safety profile and feasibility are generally favorable, these agents are also associated with immune-related adverse events (irAEs). The incidence of irAEs is relatively rare, but patients occasionally develop serious adverse events that can be fatal. When irAEs will occur and the organs that will be affected cannot be predicted, and appropriate methods for managing irAEs have not been established. Furthermore, most physicians are not familiar with the clinical management of irAEs. In order to overcome these problems, investigations to predict biomarkers of irAEs and the application of multidisciplinary team approaches are being attempted. These trials may lead to the early detection and management of irAEs through patient education. This review summarizes the current data and consensus concerning the management of irAEs induced by immunotherapy in lung cancer treatments.