BACKGROUND: To investigate the significance of preoperative fibrinogen-to-prealbumin ratio (FPR) in the prognosis of non-small cell lung cancer. METHODS: The clinical follow-up pathological data of 289 patients who underwent radical lung cancer resection and were pathologically diagnosed with non-small cell lung cancer after surgery were retrospectively analysed, and the FPR value was calculated according to the serological test results within 1 week before surgery. The cut-off value of FPR was obtained by analysing the receiver operating characteristic curve (ROC). Kaplan-Meier analysis was used to describe the survival curve, and Cox proportional hazards model was used to explore the risk factors affecting prognosis. RESULTS: When the FPR value was 10.96, the Youden index was the highest, with a sensitivity of 62.4% and a specificity of 69.6%. The cumulative five-year survival rate in the low FPR group was significantly higher than that in the high FPR group (81.4% versus 54.7%). Univariate and multivariate analyses showed that FPR level was a risk factor for prognosis. CONCLUSION: There is a correlation between FPR level and the prognosis of lung cancer patients, and early intervention should be implemented for patients with high FPR before surgery.