Lung cancer is a highly lethal malignant tumor worldwide and in China, with non-small cell lung cancer (NSCLC) accounting for approximately 85% of cases globally. In recent years, immune checkpoint inhibitor (ICI) had changed the paradigm of lung cancer treatment, either alone or in combination with chemotherapy and recomended as the first-line treatment for NSCLC. NSCLC patients often required glucocorticoid(GC) due to the cancer itself, tumor complications, or immune-related adverse event (irAE). GC had sparked debates on their impact on the therapeutic effectiveness of ICI in NSCLC patients as a substance with immunomodulatory effects. While some studies suggested that GC use did not influence patients survival, others argued the opposite. Understanding the effects of GC on immunotherapy is crucial for managing complaications in cancer patients and addressing irAE. This review explores the impact of GC on the efficacy of ICI in NSCLC patients, aiming to provide insights for clinical treatment.