['To analyze the impact of neutrophil-to-lymphocyte ratio (NLR) on survival of patients with post-operative recurrence of non-small cell lung cancer (NSCLC).', 'The clinicopathological characteristics and outcome data of 235 patients with post-operative recurrent NSCLC were collected and reviewed. The best cut-off value of NLR at recurrence was identified according to the receiver operating characteristic curve (ROC curve), and all 235 patients were therefore divided into two groups based on the NLR value. The prognostic impact of NLR on survival in patients with recurrent NSCLC was tested by univariate and multivariate analyses.', 'The NLR of 2.97 was identified as the optimal cut-off value. There was no statistically significant difference in the clinicopathological characteristics between the low NLR (NLR ≤ 2.97) and high NLR (NLR>2.97) groups at recurrence. The median post-recurrence survival of 235 patients was 13 months (range, 1-81 months). The post-recurrence 1-, 2-year survival rates were 58.4% and 32.6%, respectively. Univariate analysis showed that age at the time of operation >65 years (P = 0.009), a histological type of large cell lung cancer or sarcoma (P < 0.001), TNM stage III of the primary tumor (P = 0.043) and NLR>2.97 at recurrence (P < 0.001) were prognostic risk factors for post-recurrence survival, while preoperative NLR>2.97 was not (P = 0.104). The post-recurrence 1- and 2-year survival rates of the low recurrence NLR group were 74.7% and 43.1%, respectively, significantly higher than that of the high recurrence NLR group (35.4% and 17.2%, respectively) (P < 0.001). Cox multivariate analysis showed that age >65 (HR = 1.707, P = 0.001), TNM stage III of primary tumor (HR = 1.654, P = 0.001) and NLR>2.97 (HR = 2.859, P < 0.001) at recurrence were independent prognostic factors (P < 0.05 for all).'] Does [ Neutrophil-to-lymphocyte ratio predict the survival in patients with post-operative recurrence of non-small cell lung cancer ]?