This study aimed to quantitatively identify the prognostic and clinicopathological value of the geriatric nutritional risk index (GNRI) in non-small cell lung cancer (NSCLC) through a meta-analysis. The electronic databases PubMed, Web of Science, Embase, and Cochrane Library were thoroughly searched from inception to December 14, 2021. Pooled hazard ratios (HRs) and 95% confidence intervals (CIs) were calculated to evaluate the prognostic value of GNRI. Odds ratios (ORs) and 95%CIs were combined to estimate the clinicopathological significance of the GNRI in NSCLC. Seven studies with 2,023 patients were included in the meta-analysis. A low GNRI score was significantly associated with poor overall survival (OS) (HR = 2.01, 95%CI = 1.65-2.44, p < 0.001) and worse progression-free survival (PFS), recurrence-free survival (RFS), and cancer-specific survival (CSS) (HR = 1.81, 95%CI = 1.48-2.22, p < 0.001) in NSCLC. Furthermore, a low GNRI score was significantly associated with the histological type of non-adenocarcinoma (OR= 1.55, 95%CI = 1.19-2.03, p = 0.001) and Eastern Cooperative Oncology Group performance status (ECOG PS) ≥2 (OR= 2.81, 95%CI= 1.49-5.32, p = 0.001). A low GNRI score is a significant and effective prognostic marker for poor survival outcomes in patients with NSCLC. In addition, low GNRI score was correlated with higher ECOG PS scores.