Abstract:Immune checkpoint inhibitors have significantly improved the clinical prognosis of patients with non-small cell lung cancer (NSCLC), especially advanced NSCLC with high expression of programmed cell death ligand 1 and negative driver genes. However, there are still some patients who cannot benefit from immunotherapy, so it is necessary to explore more biomarkers that can effectively predict the efficacy of immunotherapy in NSCLC. Gut microbiome (GM) is an environmental factor that people are continuously exposed to throughout their lives. Studies have found that specific GM is strongly associated with a good prognosis of immunotherapy for a variety of solid tumors, including NSCLC. This article reviews the prognostic effects of GM and its metabolites in NSCLC immunotherapy, aiming to screen the population suitable for NSCLC immunotherapy and offering a new pattern in precision tumor treatment.